Condensed Consolidated Statements Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 54,360	$ 59,007	$ 111,305	$ 99,213
Other comprehensive income (loss), net of taxes:
Change in value of derivative instruments used as cash flow hedges, net of tax of $0, $3,874, $0, and ($2,504)	0	6,091	0	(3,820)
Reclassification - derivative settlements, net of tax of $0, $317, $0, and ($1,177)	0	506	0	(1,831)
Ineffective portion of derivatives, net of tax of $0, ($667), $0, and ($141)	0	(1,050)	0	(227)
Comprehensive income	$ 54,360	$ 64,554	$ 111,305	$ 93,335