Acquisitions Independence Bank Acquisition - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	Jan. 26, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Goodwill		$ 50,832	$ 22,950	$ 17,428
Independence Bank
Business Acquisition [Line Items]
Consideration paid	$ 79,777
Cash consideration	6,100
Cash consideration for holders of options and warrants	1,500
Equity interests issued	$ 1,300
Number of shares of common stock issued as consideration	4,480,645
Value of shares of common stock to be issued	$ 70,900
Share price (in dollars per share)	$ 15.83
Goodwill	$ 27,882