ALLL Activity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Allowance for loan and lease losses
Balance at beginning of period	$ 129,697	$ 129,753
Provision for loan losses	568	765
Charge-offs	(1,163)	(1,297)
Recoveries	969	635
Balance at end of period	130,071	129,856
Residential Real Estate
Allowance for loan and lease losses
Balance at beginning of period	14,427	14,680
Provision for loan losses	(1,149)	440
Charge-offs	(100)	(14)
Recoveries	18	25
Balance at end of period	13,196	15,131
Commercial Real Estate
Allowance for loan and lease losses
Balance at beginning of period	67,877	67,799
Provision for loan losses	(873)	(286)
Charge-offs	(253)	(445)
Recoveries	295	259
Balance at end of period	67,046	67,327
Other Commercial
Allowance for loan and lease losses
Balance at beginning of period	32,525	30,891
Provision for loan losses	3,720	1,112
Charge-offs	(324)	(694)
Recoveries	133	206
Balance at end of period	36,054	31,515
Home Equity
Allowance for loan and lease losses
Balance at beginning of period	8,998	9,963
Provision for loan losses	(793)	(459)
Charge-offs	(229)	(31)
Recoveries	173	46
Balance at end of period	8,149	9,519
Other Consumer
Allowance for loan and lease losses
Balance at beginning of period	5,870	6,420
Provision for loan losses	(337)	(42)
Charge-offs	(257)	(113)
Recoveries	350	99
Balance at end of period	$ 5,626	$ 6,364