Other Comprehensive Income (Details 2) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Realized gain on sale of investment securities	$ 26	$ 498	$ 531	$ 1,122
Interest expense derivative deposits	(6,403)	(4,530)	(12,233)	(8,673)
Income tax benefit (expense)	(17,382)	(15,069)	(32,700)	(29,482)
Amounts reclassified from accumulated other comprehensive income	(286)	(744)	(970)	(1,118)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Realized gain on sale of investment securities	26	498	531	1,122
Interest expense derivative deposits	439	482	1,019	482
Interest expense derivative borrowings		260		260
Income tax benefit (expense)	(179)	(496)	(580)	(746)
Amounts reclassified from accumulated other comprehensive income	$ 286	$ 744	$ 970	$ 1,118