CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (17,507)	$ (16,132)
Adjustments to reconcile net loss to net cash provided by operating activities:
Unrealized losses on commodity derivative contracts, net	18,166	26,589
Asset retirement accretion	134	47
Depreciation, depletion, and amortization	28,027	18,618
Share-based compensation		650
Accrued interest on mandatorily redeemable convertible preferred units	762
Amortization of deferred financing costs	216	179
Change in operating assets and liabilities:
Accounts receivable - oil and gas sales	2,877	(3,455)
Accounts receivable - other	2,747	412
Prepayments and other assets	(1,918)	(352)
Inventory	(495)	(77)
Accounts payable	161	(7,028)
Accrued liabilities	1,186	7,282
Other	(40)	(3)
Net cash provided by operating activities	34,316	26,730
CASH FLOWS FROM INVESTING ACTIVITIES:
Investment in property and equipment	(72,466)	(52,392)
Net cash used in investing activities	(72,466)	(52,392)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from long-term borrowings		18,000
Proceeds from issuance of mandatorily redeemable convertible preferred units	40,000
Cash received for units		170
Other		(300)
Net cash provided by financing activities	40,000	17,870
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1,850	(7,792)
Cash and cash equivalents, beginning of period	7,344	11,917
Cash and cash equivalents, end of period	9,194	4,125
SUPPLEMENTAL INFORMATION:
Non-cash transactions - investments in property and equipment accrued - not paid	82,845	22,100
Cash paid for interest, net of capitalized interest of $0.7 million and $0.6 million, respectively	$ 1,106