Additional Balance Sheet Detail (Tables)

3 Months Ended

Mar. 31, 2013

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Components of Selected Balance Sheet Accounts

The following table summarizes components of selected balance sheet accounts as of the dates presented:

	As of
	March 31,		December 31,
	2013		2012
Other current assets:
Tubular inventory and well materials	$	2,879	$	4,033
Prepaid expenses	1,082		562
	$	3,961	$	4,595
Other assets:
Debt issuance costs	$	12,613	$	13,186
Assets of supplemental employee retirement plan (“SERP”)	3,401		3,237
Other	1,278		1,511
	$	17,292	$	17,934
Accounts payable and accrued liabilities:
Trade accounts payable	$	31,335	$	37,835
Drilling costs	43,858		37,703
Royalties	13,559		14,390
Production and franchise taxes	4,820		2,874
Compensation - related	2,713		6,853
Interest	19,072		5,828
Preferred stock dividends	1,725		1,687
Other	4,885		4,485
	$	121,967	$	111,655
Other liabilities:
Firm transportation obligation	$	13,870	$	14,333
Asset retirement obligations (“AROs”)	4,551		4,513
Defined benefit pension obligations	1,786		1,821
Postretirement health care benefit obligations	2,699		2,634
Deferred compensation - SERP obligation and other	3,469		3,310
Other	2,143		2,290
	$	28,518	$	28,901