Acquisitions Business Acquisition, Pro Forma Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Interest Income	$ 301,699	$ 289,330
Business Acquisition, Pro Forma Non Interest Income	137,793	123,282
Business Acquisition, Pro Forma Revenue	439,492	412,612
Business Acquisition, Pro Forma Net Income (Loss)	98,674	$ 88,847
Pro Forma Acquisition Expenses, Net of Tax	$ 1,834