Income Taxes Deferred Tax Assetss And Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Allowance for credit losses	$ 62,846	$ 68,407
Postretirement and defined benefit plans	13,070	16,017
State loss carryforwards	11,170	12,960
Other accrued expenses	11,839	12,486
Other-than-temporary impairment of investments	5,501	8,126
Other accrued expenses	7,142	7,335
Unrealized holding losses on securities available for sale	3,250	0
Other	10,165	8,433
Total gross deferred tax assets	124,983	133,764
Deferred Tax Liabilities, Gross [Abstract]
Mortgage servicing rights	14,582	15,004
Direct leasing	20,309	12,399
Acquisition premiums/discounts	8,897	8,200
Premises and equipment	5,955	7,897
Unrealized holding gains on securities available for sale	0	3,949
Intangible assets	1,614	1,382
Other	9,593	7,960
Total gross deferred tax liabilities	60,950	56,791
Net deferred tax asset, before valuation allowance	64,033	76,973
Valuation allowance	(8,359)	(10,187)
Net deferred tax asset	55,674	66,786
State and local operating loss carryforwards	424,000	$ 451,000
Capital loss carryforwards	3,400
Deferred tax assets other than temporary impairment losses investment securities	$ 5,300