Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net Income	$ 100,232	$ 97,707	$ 84,167
Other comprehensive income, net of tax:
Unrealized loss on securities available for sale	(840)	(2,280)	(254)
Reclassification adjustment for net gains included in net income	(336)	(716)	(1,352)
Total unrealized loss on investment securities	(1,176)	(2,996)	(1,606)
Unrealized gain (loss) on derivatives	2,794	(934)	(850)
Reclassification adjustment for amounts included in net income	(987)	1,358
Total unrealized gain (loss) on derivatives	1,807	424	(850)
Other comprehensive income (loss)	631	(2,572)	(2,456)
Comprehensive Income	$ 100,863	$ 95,135	$ 81,711