Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net income	$ 80,362	$ 58,860	$ 13,719
Gain (loss) on cash flow hedges, net of tax expense (benefit) of $1,175, $195 and $(626)	1,893	361	(1,019)
Comprehensive income	$ 82,255	$ 59,221	$ 12,700