15. Commitments and Contingencies

We have issued the following guarantees that are not recorded on our accompanying balance sheet (dollars in thousands):

	Term	Maximum Potential Undiscounted Payments as of March 31, 2015
Performance guarantees through letters of credit(1)	2015-2019	$	149,362
Standby letters of credit	2015	12,910
Commercial letters of credit	2015	3,426
Bid bonds and performance bonds(1)	2015-2023	78,602
Maximum potential undiscounted payments		$	244,300

(1)

We have issued guarantees to third parties to ensure performance of our obligations, some of which may be fulfilled by third parties.

As part of an acquisition in 2001, we may be required to make contingent payments of up to $46 million to the seller, depending on our realization of certain U.S. federal tax benefits through the year 2015. To date, we have not realized any such benefits that would require a payment and we do not anticipate realizing any such benefits that would require a payment before the year 2016.

See Note 3 and Note 7 for a discussion of our gain contingencies related to assets that were expropriated in Venezuela.

In addition to U.S. federal, state, local and foreign income taxes, we are subject to a number of taxes that are not income-based. As many of these taxes are subject to audit by the taxing authorities, it is possible that an audit could result in additional taxes due. We accrue for such additional taxes when we determine that it is probable that we have incurred a liability and we can reasonably estimate the amount of the liability. As of March 31, 2015 and December 31, 2014, we had accrued $9.1 million and $9.2 million, respectively, for the outcomes of non-income based tax audits. We do not expect that the ultimate resolutions of these audits will result in a material variance from the amounts accrued. We do not accrue for unasserted claims for tax audits unless we believe the assertion of a claim is probable, it is probable that it will be determined that the claim is owed and we can reasonably estimate the claim or range of the claim. We do not have any unasserted claims from non-income based tax audits that we have determined are probable of assertion. We also believe the likelihood is remote that the impact of potential unasserted claims from non-income based tax audits could be material to our consolidated financial position, but it is possible that the resolution of future audits could be material to our results of operations or cash flows for the period in which the resolution occurs.

Our business can be hazardous, involving unforeseen circumstances such as uncontrollable flows of natural gas or well fluids and fires or explosions. As is customary in our industry, we review our safety equipment and procedures and carry insurance against some, but not all, risks of our business. Our insurance coverage includes property damage, general liability and commercial automobile liability and other coverage we believe is appropriate. In addition, we have a minimal amount of insurance on our offshore assets. We believe that our insurance coverage is customary for the industry and adequate for our business; however, losses and liabilities not covered by insurance would increase our costs.

Additionally, we are substantially self-insured for workers’ compensation and employee group health claims in view of the relatively high per-incident deductibles we absorb under our insurance arrangements for these risks. Losses up to the deductible amounts are estimated and accrued based upon known facts, historical trends and industry averages.

Litigation and Claims

In 2011, the Texas Legislature enacted changes related to the appraisal of natural gas compressors for ad valorem tax purposes by expanding the definitions of “Heavy Equipment Dealer” and “Heavy Equipment” effective from the beginning of 2012 (the “Heavy Equipment Statutes”). Under the revised statutes, we believe we are a Heavy Equipment Dealer, that our natural gas compressors are Heavy Equipment and that we, therefore, are required to file our ad valorem tax renditions under this new methodology. A large number of appraisal review boards denied our position, and we filed petitions for review in the appropriate district courts.

During 2013 and 2014, we were party to three Heavy Equipment Statutes cases tried and completed in Texas state district courts. In each case the court held that the revised Heavy Equipment Statutes apply to natural gas compressors. However, in each case the court further held that the revised Heavy Equipment Statutes are unconstitutional as applied to natural gas compressors, which is favorable to the county appraisal districts. We continue to believe that the revised statutes are constitutional as applied to natural gas compressors and have appealed the courts’ decisions in our cases. All three of these cases have been appealed. For two of these appeals, oral arguments were made before the Eighth Court of Appeals in El Paso, Texas on October 9, 2014. No decision has been issued. The third appeal was argued before the Fourteenth Court of Appeals in Houston, Texas on February 12, 2015. No decision has been issued. In a fourth state district court case, both parties’ respective motions for summary judgment are pending and we have yet to receive the court’s decision. In a fifth state district court case, the court denied both parties’ respective motions for summary judgment concerning the 2012 tax year, consolidated the 2012 tax year case with a 2013 tax year case, and set a trial date for the consolidated case of August 10-11, 2015.

As a result of the new methodology, our ad valorem tax expense (which is reflected in our condensed consolidated statements of operations as a component of cost of sales (excluding depreciation and amortization expense)) includes a benefit of $3.7 million during the three months ended March 31, 2015. Since the change in methodology became effective in 2012, we have recorded an aggregate benefit of $30.6 million as of March 31, 2015, of which approximately $6.2 million has been agreed to by a number of appraisal review boards and county appraisal districts and $24.4 million has been disputed and is currently in litigation. Recognizing the similarity of the issues and that these cases will ultimately be resolved by the Texas appellate courts, we have reached, or intend to reach, agreements with some of the appraisal districts to stay or abate certain of these pending district court cases. If we are unsuccessful in our litigation with the appraisal districts, we would be required to pay ad valorem taxes up to the aggregate benefit we have recorded, and the additional ad valorem tax payments may also be subject to substantial penalties and interest. Also, if we are unsuccessful in our litigation with the appraisal districts, or if legislation is enacted in Texas that repeals or alters the Heavy Equipment Statutes such that in the future we do not qualify as a Heavy Equipment Dealer or our compressors do not qualify as Heavy Equipment, then we would likely be required to pay these ad valorem taxes under the old methodology going forward, which would increase our quarterly cost of sales expense up to approximately the amount of our then most recent quarterly benefit recorded, and as a result impact our future results of operations and cash flows.

In the ordinary course of business, we are also involved in various other pending or threatened legal actions. While management is unable to predict the ultimate outcome of these actions, it believes that any ultimate liability arising from any of these other actions will not have a material adverse effect on our consolidated financial position, results of operations or cash flows. However, because of the inherent uncertainty of litigation and arbitration proceedings, we cannot provide assurance that the resolution of any particular claim or proceeding to which we are a party will not have a material adverse effect on our consolidated financial position, results of operations or cash flows.