Goodwill, Core Deposit Premium and Other Intangible Assets (Changes in capitalized mortgage and commercial servicing rights) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Servicing Asset at Fair Value, Amount [Roll Forward]
Valuation allowance on commercial servicing rights	$ 5	$ 0	$ (41)	$ 0
Mortgage servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of period			30,314	24,984
Originations			9,323	11,062
Amortization			(7,795)	(6,446)
Balance at end of period	31,842	29,600	31,842	29,600
Fair value of servicing rights	38,127	40,166	$ 38,127	$ 40,166	$ 40,900
Servicing rights, net to servicing portfolio (as a percent)			0.75%	0.75%
Commercial servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of period			$ 4,611	$ 0
Purchased commercial servicing rights			190	4,255
Originations			533	704
Amortization			(1,229)	(802)
Valuation allowance on commercial servicing rights			(41)	0
Balance at end of period	4,064	4,157	4,064	4,157
Fair value of servicing rights	$ 4,397	$ 4,412	$ 4,397	$ 4,412
Servicing rights, net to servicing portfolio (as a percent)			2.38%	2.33%