Consolidated Statements Of Cash Flows (USD $) In Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities
Net loss	$ (152,766)	$ (121,380)
Adjustments to reconcile net loss to net cash provided by operating activities -
Depreciation, depletion and amortization	231,353	158,621
Impairment of oil and gas properties	45,704	15,078
Gain on exchange/disposal of properties	(1,000)	(27,020)
Accretion of asset retirement obligation	11,157	10,419
Deferred income tax expense (benefit)	38,784	(76,196)
Derivative income	(82,286)	(14,088)
(Gain) loss on debt extinguishment	(1,091)	21,829
Stock-based compensation	4,669	5,366
Amortization of deferred revenue		(19,336)
Noncash interest expense	29,015	22,756
Other noncash items, net	264	509
Changes in assets and liabilities
Accounts receivable and other current assets	16,514	(13,476)
Accounts payable and accruals	(5,095)	39,908
Other assets and liabilities	(6,593)	(601)
Net cash provided by operating activities	128,629	2,389
Cash flows from investing activities
Additions to oil and gas properties	(312,196)	(498,625)
Proceeds from disposition of properties	1,000	17,053
Increase (decrease) in restricted cash	17,610	(16,850)
Net cash used in investing activities	(293,586)	(498,422)
Cash flows from financing activities
Proceeds from senior second lien notes		1,492,965
Proceeds from first lien term loans	59,400	147,000
Proceeds from term loan facility-ATP Titan assets	91,000	143,250
Proceeds from term loans		46,000
Payments of term loans	(18,046)	(1,262,610)
Deferred financing costs	(4,536)	(59,294)
Proceeds from other long-term obligations	70,327	171,136
Payments of other long-term obligations	(130,882)	(69,091)
Distributions to noncontrolling interest	(36,132)	(10,688)
Proceeds from preferred stock issuances, net of costs	149,781
Purchase of capped-call options on ATP common stock	(26,500)
Preferred stock dividends	(8,371)	(8,448)
Derivative contracts, net	66,009
Other financings, net	(30,625)
Exercise of stock options/warrants	307	3,580
Net cash provided by financing activities	181,732	593,800
Effect of exchange rate changes on cash and cash equivalents	705	203
Increase in cash and cash equivalents	17,480	97,970
Cash and cash equivalents, beginning of year	154,695	108,961
Cash and cash equivalents, end of period	172,175	206,931
Noncash investing and financing activities
Increase in noncash property additions	20,643	112,927
Net property additions-nonmonetary exchange		11,778
Asset retirement costs capitalized		$ 1,258