Interest And Other Income (Components Of Interest And Other Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Interest And Other Income [Abstract]
Alaskan Petroleum Production Tax credits and refunds	$ 11,846	[1]	$ 27,452	[1]
Equity interest in income of unconsolidated affiliate	6,981		298
Third-party income from vertical integration services	6,549	[2]	2,878	[2]
Other income	1,641		638
Deferred compensation plan income	1,374		867
Interest income	57		187
Total interest and other income	$ 28,448		$ 32,320

[1] The Company earns Alaskan Petroleum Production Tax ("PPT") credits on qualifying capital expenditures. The Company recognizes income from PPT credits when they are realized through cash refunds or as reductions in production and ad valorem taxes if realizable as offsets to PPT expense.

[2] Third-party income from vertical integration services represents the third party working interests' share of earnings associated with Company-provided fracture stimulation, drilling and related services.