Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Consolidated Statements of Comprehensive Income
Net income	$ 32,019	$ 33,233	$ 101,756	$ 114,597
Other comprehensive income (loss), net of tax
Net unrealized holding gains (losses) on securities available for sale arising during period (tax effects of $9,409, $(7,888), $7,855 and $23,898)	17,474	(14,649)	14,587	44,382
Reclassification adjustment for gains (losses) on securities available for sale included in net income (tax effects of $0, $2,256, $(150) and $(449))		4,190	(278)	(834)
Reclassification adjustment for impairment charges on available for sale securities included in net income (tax effects of $87, $96, $245 and $193)	162	177	455	359
Other comprehensive income (loss), net of tax	17,636	(10,282)	14,764	43,907
Comprehensive income	$ 49,655	$ 22,951	$ 116,520	$ 158,504