We occupy various facilities and lease certain equipment under various lease agreements. The minimum rental commitments under non-cancelable operating leases, with lease terms in excess of one year subsequent to December 31, 2012, are as follows (in thousands):


2013	$	1,076
2014		1,047
2015		941
2016		941
2017		697
Thereafter		1,399

		2012			2011			2010

Rent expense		$	3,103		$	1,369		$	1,158

As of December 31, we had outstanding capital purchase commitments which consisted of (in thousands):

	2012		2011

Capital commitments
Equipment	$	20,317	$	8,637
Land	$	23,700	$	23,700
Supplies and services
Coal purchase commitments	$	28,633	$	5,652
Transportation agreements	$	159,398	$	135,080
Materials and supplies	$	24,552	$	29,641

On July 9, 2012, our wholly-owned indirect subsidiary, Western Minerals LLC ("Western Minerals"), filed a lawsuit in the U.S. District Court for the District of Montana (Billings Division), against KCP Inc. ("KCP"), its 50% joint-venture partner in the Decker mine in Montana. Western Minerals also named as defendants KCP's parent companies, Ambre Energy North America, Inc. ("Ambre N.A.") and Ambre Energy Limited ("Ambre Limited" and together with Ambre N.A. "Ambre"). In its complaint, Western Minerals alleges that KCP and Ambre are engaging in self-dealing and other wrongful conduct in breach of the Decker joint venture agreement and other legal duties owed to the joint venture and its 50/50 owners. Western Minerals asserts claims for breach of contract, breach of implied covenant of good faith and fair dealing, breach of fiduciary duty, aiding and abetting breach of fiduciary duty, civil conspiracy, and a request for an accounting of, among other things, unauthorized Decker expenditures and Ambre's proposed self-dealing transactions concerning sales of Decker coal to Ambre and its affiliates. Western Minerals seeks both unspecified monetary damages and injunctive relief.

On August 23, 2012, KCP and Ambre N.A., filed an amended answer to Western Minerals' complaint, replacing the original answer they filed on July 30, 2012. In their amended answer, KCP and Ambre N.A. deny the principal allegations of Western Minerals. Additionally, KCP asserted six counterclaims against Western Minerals: breach of contract, breach of the covenant of good faith and fair dealing, breach of fiduciary duty, dissolution of the joint venture, civil conspiracy and a request for declaratory judgment. KCP also asserted two third-party claims against CPE Inc. for tortious interference of economic relations and civil conspiracy involving unnamed "John Doe" defendants. In general, KCP alleges that Western Minerals is frustrating the operation of the Decker mine to benefit Cloud Peak Energy's Spring Creek mine and export opportunities. Aside from the request that the court disassociate and expel Western Minerals from the Decker mine joint venture, KCP also seeks unspecified monetary damages in its counterclaims. Western Minerals and Cloud Peak Energy believe KCP's claims are without merit and intend to vigorously defend them. On September 14, 2012, Ambre Limited filed a motion to dismiss arguing that it was not subject to the jurisdiction of the Montana federal court. Western Minerals has filed a response to that motion and the court has not yet issued a ruling.

On December 5, 2012, we and Ambre Limited announced that our respective companies have entered into agreements for Ambre Limited to purchase our 50% interest in the Decker mine and related assets and assume all reclamation liabilities. The agreements will also provide for the joint resolution and dismissal of the pending Decker litigation upon closing of the transaction. Closing is expected to occur in the first half of 2013, subject to various closing conditions.

Challenges Against the BLM's Leasing Process; Intervention by Cloud Peak Energy and Others —On May 3, 2010, WildEarth Guardians, Defenders of Wildlife and Sierra Club (collectively, "WildEarth") and the Powder River Basin Resource Council ("PRBRC") filed appeals with the Interior Board of Land Appeals ("IBLA") regarding the U.S. Bureau of Land Management's ("BLM") decision to offer the West Antelope II ("WAII") coal tracts for lease. On June 29, 2010, WildEarth voluntarily dismissed its appeal. On July 13, 2010, WildEarth filed a complaint in the United States District Court for the District of Columbia ("D.C. District Court") challenging the BLM's decision. On November 2, 2010, the IBLA issued a decision in PRBRC's appeal, rejecting all of PRBRC's arguments and affirming the BLM's decision in all respects. On January 3, 2011, PRBRC filed a complaint in the D.C. District Court appealing the IBLA decision. On May 8, 2011, the D.C. District Court consolidated the WildEarth and PRBRC challenges. Antelope Coal LLC, a wholly-owned subsidiary of CPE Resources, (along with the National Mining Association and the State of Wyoming) intervened in the consolidated action on the side of the BLM. In the consolidated action, WildEarth and PRBRC requested that the court vacate the BLM's authorization, sale and issuance of the WAII leases and enjoin any coal mining activity on the leases until the BLM and the U.S. Fish and Wildlife Service had undertaken additional environmental analysis requested by the plaintiff organizations.

Award of LBAs to Cloud Peak Energy—On May 11, 2011, the BLM held a competitive sale for the WAII North Tract. On June 15, 2011, the BLM held a competitive sale for the WAII South Tract. Antelope Coal LLC was the successful high bidder in both sales, and the BLM issued leases to Antelope Coal LLC for the North Tract effective July 1, 2011 and for South Tract effective September 1, 2011.

District Court Rejection of Challenges; Appeal by Plaintiffs—On July 30, 2012, the D.C. District Court rejected WildEarth's and PRBRC's consolidated challenge to the IBLA decision and denied their request that the court vacate the WAII leases as well as their requested injunction against coal mining activity on the leases. On September 25, 2012 and September 26, 2012, PRBRC and WildEarth, respectively, filed notices of appeal in the United States Circuit Court of Appeals for the District of Columbia. Both groups are appealing the decision issued by the D.C. District Court and have not yet specified what relief they are seeking from the appellate court. Antelope Coal LLC is a respondent-intervenor in the consolidated appeal. Any adverse outcome of the appeal could adversely impact or delay our ability to mine the coal subject to the leases.

We are involved in other legal proceedings arising in the ordinary course of business and may become involved in additional proceedings from time to time. We believe that there are no other legal proceedings pending that are likely to have a material adverse effect on our consolidated financial condition, results of operations or cash flows. Nevertheless, we cannot predict the impact of future developments affecting our claims and lawsuits, and any resolution of a claim or lawsuit or an accrual within a particular fiscal period may adversely impact our results of operations for that period. In addition to claims and lawsuits against us, our LBAs, permits, and other industry regulatory processes and approvals may also be subject to legal challenges that could adversely impact our mining operations and results, as discussed above.

Our income tax calculations are based on application of the respective U.S. federal or state tax law. Our tax filings, however, are subject to audit by the respective tax authorities. Accordingly, we recognize tax benefits when it is more likely than not a position will be upheld by the tax authorities. To the extent the final tax liabilities are different from the amounts originally accrued, the increases or decreases are recorded as income tax expense.

Several audits involving our non-income based taxes currently are in progress. We have provided our best estimate of taxes and related interest and penalties due for potential adjustments that may result from the resolution of such tax audits.

Approximately 93%, 81% and 83% of our revenue for the years ended December 31, 2012, 2011, and 2010, respectively, were under multi-year contracts. While the majority of the contracts are fixed-price contracts, certain contracts have adjustment provisions for determining periodic price changes. There was no single customer that represented 10% or more of consolidated revenue in 2012, 2011, or 2010. We generally do not require collateral or other security on accounts receivable because our customers are comprised primarily of investment grade electric utilities. The credit risk is controlled through credit approvals and monitoring procedures.

In the normal course of business, we are party to guarantees and financial instruments with off-balance sheet risk, such as bank letters of credit, performance or surety bonds and indemnities, which are not reflected on the consolidated balance sheet. In our past experience, virtually no claims have been made against these financial instruments. Management does not expect any material losses to result from these guarantees or off-balance-sheet instruments.

U.S. federal and state laws require we secure certain of our obligations to reclaim lands used for mining and to secure coal lease obligations. The primary method we have used to meet these reclamation obligations and to secure coal lease obligations is to provide a third-party surety bond, typically through an insurance company, or provide a letter of credit, typically through a bank. Specific bond and/or letter of credit amounts may change over time, depending on the activity at the respective site and any specific requirements by federal or state laws. As of December 31, 2012, we had $610.3 million of surety bonds outstanding (including our proportional share of the Decker mine) to secure certain of our obligations to reclaim lands used for mining and to secure coal lease obligations.