Business Combinations - Focus Business Bank - Estimated Fair Values of the Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Aug. 20, 2015
Assets acquired:
Goodwill	$ 45,664	$ 45,664	$ 44,898
Focus Business Bank
Assets acquired:
Cash and cash item				$ 5,651
Federal funds sold and deposits in other financial institutions				168,415
Securities available-for-sale				53,940
Securities held-to-maturity				8,665
Loans held-for-sale				4,416
Net loans				170,353
Goodwill				32,620
Core deposit intangible asset				6,285
Corporate owned life insurance				7,067
Other assets, net				20,250
Total assets acquired				477,662
Liabilities assumed:
Deposits				405,123
Other liabilities				5,981
Total liabilities				411,104
Net assets acquired				$ 66,558