Income Taxes Deferred Tax Assets And Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets:
Tax credit carryforwards	$ 43,133	$ 27,615
Allowance for credit losses	37,081	37,906
State loss carryforwards	16,324	11,605
Other accrued expenses	8,797	7,232
Deferred compensation	7,752	7,064
Tax credit investments	6,799	4,529
Stock-based compensation	2,930	2,743
Postretirement and defined benefit plans	599	5,079
OTTI	462	1,803
Unrealized holding losses on securities	0	12,489
Other	3,784	3,855
Total gross deferred tax assets	127,661	121,920
Deferred Tax Liabilities, Gross [Abstract]
Equipment lease financing	42,273	31,466
MSRs	8,686	8,560
Premises and equipment	6,282	3,579
Acquisition premiums/discounts	5,266	5,294
Unrealized holding gains on securities available for sale	4,223	0
Intangible assets	1,136	1,292
Other	12,387	12,178
Total gross deferred tax liabilities	80,253	62,369
Net deferred tax asset, before valuation allowance	47,408	59,551
Valuation allowance	(16,324)	(11,605)
Net deferred tax asset	31,084	47,946
State and local operating loss carryforwards	392,000	$ 347,300
Tax credit carryforwards related to TCIs	$ 43,000