Condensed Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	$ 1,100		$ 1,900		$ 2,100
Net earnings	118,985		113,430		385,405
Other comprehensive income, net of tax:
Unrealized changes in fair value of cash flow hedges	(1,542)	[1]	(3,116)	[1]	(3,276)	[1]
Unrealized changes in fair value of available-for-sale securities	0		(117)		117
Realized losses on cash flow hedges reclassified from AOCI into earnings	854	[2]	3,040	[2]	0
Other Comprehensive Income Amortization Of Realized Gain Loss And Unrealized Holding Changes On Fair Value Of Discontinued Cash Flow Hedges Net Of Tax	0		0		10,721	[3]
Foreign currency translation adjustment	1,487		(331)		6
Other comprehensive income (loss)	799		(524)		7,568
Comprehensive income	119,784		112,906		392,973
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Tax	(500)		(2,000)
Other Comprehensive Income Amortization Of Realized Gain Loss And Unrealized Holding Changes On Fair Value Of Discontinued Cash Flow Hedges, Tax					$ (6,600)

[1] Presented net of tax of $1.1 million, $1.9 million and $2.1 million for the years ended December 31, 2012, 2011 and 2010, respectively.

[2] Presented net of tax of $(0.5) million and $(2.0) million for the years ended December 31, 2012 and 2011, respectively.

[3] Presented net of tax of $(6.6) million for the year ended December 31, 2010.