Other Intangible Assets (Amortization Expense of Core Deposit Intangible Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Carrying amount, accumulated amortization and amortization expense of core deposit intangible assets
Carrying amount	$ 38,104	$ 33,080
Amortization and impairment of intangible assets	8,244	3,545	$ 3,492
Core deposit intangible assets [Member]
Carrying amount, accumulated amortization and amortization expense of core deposit intangible assets
Gross original amount	40,055	31,550
Accumulated amortization	13,401	10,687
Carrying amount	26,654	20,863
Amortization and impairment of intangible assets	$ 4,142	$ 2,029