Cyril Ibhagbosoria Aburime, petitioner, Appellant, vs. Becky May Aburime, Respondent.

may not be cited except as provided by

Minn. Stat. § 480 A. 08, subd. 3 (1996).

 STATE OF MINNESOTA

 IN COURT OF APPEALS

 C9-97-2239

Robert Huffman,

Respondent,

vs.

Premis Corporation,

Appellant.

 Filed July 7, 1998

 Affirmed

 Toussaint, Chief Judge

Hennepin County District Court

File No. 977330

William H. Henney, 5101 Thimsen Avenue, Suite 200, Minnetonka, MN 55345 (for respondent)

John M. Elliott, Sandra L. Schlafge, Pillsbury Center South, Suite 600, 220 South Sixth Street, Minneapolis, MN 55402 (for appellant)

Considered and decided by Toussaint, Chief Judge, Randall, Judge, and Holtan, Judge.[1]

 U N P U B L I S H E D O P I N I O N

 TOUSSAINT, Chief Judge

Appellant Premis Corporation (Premis) challenges a district court judgment awarding sales commissions to respondent Robert D. Huffman. In September 1994, Huffman was employed by Premis as a sales representative. In June 1996, he voluntarily resigned his position. A dispute arose between Huffman and Premis's Chief Executive Officer (CEO), Francis Biermeier, over unpaid salary and commissions that Huffman alleged were earned and owing prior to his voluntary resignation. Huffman commenced an action against Premis in conciliation court. He won a judgment in the amount of $7528 and Premis petitioned for removal to district court.

The district court concluded that (1) a unilateral contract existed between Huffman and Premis; (2) the offer letter was definite and specific in conveying the terms of Huffman's employment; (3) Huffman's testimony was more credible than that of Premis CEO, Francis Biermeier; and (4) Huffman was entitled to statutory and attorney fees. Because the district court did not err in concluding that (1) Premis's employment offer letter to Huffman constituted a unilateral contract and (2) there was sufficient evidence in the record to support the award of post-termination sales commissions, statutory penalties and attorney fees, we affirm.

 D E C I S I O N

"Whether a contract is ambiguous is a legal determination in the first instance." Blattner v. Forster, 322 N.W.2d 319, 321 (Minn. 1982). A reviewing court is not bound by and need not give deference to a trial court's decision on a purely legal issue. Frost-Benco Elec. Ass'n v. Minnesota Pub. Utils. Comm'n, 358 N.W.2d 639, 642 (Minn. 1984). However, findings of fact will not be set aside unless clearly erroneous and due regard will be given to the opportunity of the trial judge to determine the credibility of the witnesses. Minn. R. Civ. P. 52.01. Furthermore, absent an abuse of discretion, we will not reverse a trial court's award of attorney fees. Becker v. Alloy Hardfacing & Eng'g Co., 401 N.W.2d 655, 661 (Minn. 1987).

1. The Earned Commissions

Premis argues that the district court erred in concluding that Huffman's employment offer letter constituted a unilateral contract whereby Huffman was entitled to receive post-termination commissions. It contends that the language in the letter is vague and indefinite and does not suggest that (1) Huffman "earned" commission at the point of sale or (2) was entitled to earned commissions after his voluntary departure from the company.

Whether a contract exists is a question of law to be determined by the court. Hunt v. IBM Mid Am. Employees Federal Credit Union, 384 N.W.2d 853, 856 (Minn. 1986). "[A] promise of employment on particular terms of unspecified duration, if in [the] form of an offer, and if accepted by the employee, may create a binding unilateral contract." Pine River State Bank v. Mettille, 333 N.W.2d 622, 626 (Minn. 1983). The requirements of a unilateral contract include: a definite offer, communication to the offeree, acceptance by the employee, and consideration. Pine River, 333 N.W.2d at 626-27. Furthermore, the offer must contain terms definite in form to enable the fact-finder to interpret and apply them. Hunt, 384 N.W.2d at 857; Pine River, 333 N.W.2d at 626. A determination of whether a proposal is an offer must be based on the outward manifestations of the parties, not their subjective intentions. Hunt 384 N.W.2d at 857. Furthermore, Minnesota law is willing to recognize, in an appropriate case, the existence of an express convenant of good faith and fair dealing where the elements of a unilateral contract are met. Id. at 858-9.

a. The Offer Letter

At trial, Huffman introduced into evidence the offer letter he received from Larson, Premis's former Vice President of Sales and Marketing, outlining the terms of his employment. The letter stated in part:

*Your territory will be the United States until another representative is hired. At that time you will have an active role in laying out territory assignments for future sales. You will keep your existing customer base when another person joins the sales team.

* * *

*You will take over all existing customers except the USPS account and the Truck Stops hardware business just signed. You will have all future business with the Truck Stops account. You will receive a 5% commission on gross margins for business sold to existing accounts. * * *

*On all new customer business that you sign you will receive a 10% commission on the gross margins of the total sale. * * * Commissions to be paid monthly upon payment of the contract.

Premis introduced Exhibit 2 B "Compensation Plan," a document purporting to set forth the requirements of when a commission has been "earned" by a sales representative. However, both Larson and Huffman testified they had not seen this formal document until trial. The district court determined that the letter specifically stated that "Huffman will recover when the business is sold to the existing accounts." The district court then concluded that the language of the offer letter was specific and definite to constitute a unilateral contract.

On review of the record, we cannot say the district court erred in concluding that (1) the terms of the offer letter were specific and definite to constitute a unilateral contract and (2) under the terms of the offer letter, Huffman earned commissions at the point of sale. The language of the letter indicates that Huffman was to receive a commission when either he "signed" or "sold" business for Premis. We observe there is no language indicating that Huffman's entitlement to a commission hinged on the installation of the product or collection on the invoice. Furthermore, although the letter states that "[c]ommissions to be paid monthly upon payment of the contract," we conclude that this language only denotes the terms of the payment schedule for earned commissions, and does not describe "when a commission has been earned."

b. The Testimony

At trial, the district court observed that Huffman testified that he was not aware of any corporate policy preventing him from collecting any commissions that were earned prior to his voluntary resignation. The court also noted that Larson corroborated Huffman's testimony. Moreover, the court observed that Larson indicated that he was not made aware of this policy and was not shown the "compensation plan" document until he was deposed for this case. Further, Larson testified that as a sales representative, Huffman was not required to collect on invoices or install equipment. Rather, execution of the sales agreement concluded Huffman's responsibilities. The district court then concluded that it was highly unlikely that Huffman would have voluntarily left his employment had he known that he would not receive payment of his commissions on such large outstanding accounts.

Under these circumstances, we hold that the district court did not err in concluding that the testimony of Huffman was highly credible. At the time Huffman was hired, both he and Larson testified they were unaware of any policy prohibiting the collection of earned commissions upon a voluntary termination from the company. We also observe that all of the documents surrounding payment of post-termination commissions surfaced only after this action was commenced. Furthermore, neither Huffman nor Larson were aware of Premis's position that commissions were not earned by sales representatives upon the signing of the sales contract. Because credibility determinations are well within the providence of the district court, we cannot say the determination of the district court was in error. See Markowitz v. Ness, 413 N.W.2d 843, 845 (Minn. App. 1987)(witness credibility determinations left to the trier of fact).

2. Attorney and Statutory Fees

Premis also argues the district court erred in awarding statutory and attorney fees. Granting of attorney fees is largely within the district court's discretion. Becker v. Alloy Hardfacing & Eng'g Co., 401 N.W.2d 655, 661 (Minn. 1987). Minn. Stat. § 181.14 (1996) provides in part:

When any such employee, not having a contract for a definite period of service, quits or resigns employment, the wages or commissions earned and unpaid at the time the employee quits or resigns shall become due and payable within five days * * *

Furthermore, Minn. Stat. § 181.171, subd. 3 (1996) provides in part:

the court shall order an employer who is found to have committed a violation [of Minn. Stat. § 181.14] to pay the aggrieved party reasonable costs, disbursements, witness fees, and attorney fees.

Because we conclude the district court did not err in determining that earned commissions were unpaid and owing at the time of Huffman's voluntary resignation, the award of statutory and attorney fees was proper.

  Affirmed.

[1] Retired judge of the district court, serving as judge of the Minnesota Court of Appeals by appointment pursuant to Minn. Const. art. VI, § 10.