Income Taxes (Components of Deferred Tax Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
ComponentsOfDeferredTaxAssetsAbstract
Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts	$ 97,682	$ 84,959
Deferred Tax Assets Acquired Loans And Other Real Estate Valuation Adjustments	10,457	11,120
Deferred Tax Assets Operating Loss And Capital Net Carryforwards	5,169	9,686
Deferred Tax Assets Tax Credit Carryforwards Alternative Minimum Tax	15,672	15,799
Deferred tax asset acquired portfolio	35,293	36,237
Deferred Tax Assets Indemnification Asset	0	5,344
Other deferred allowance tax assets	858	1,547
Deferred Tax Assets Other	5,304	5,116
Deferred Tax Assets Gross	170,435	169,808
Components Of Deferred Tax Liabilities Abstract
Deferred Tax Liability Fdic Assisted Acquisition	(24,564)	(25,862)
Deferred tax liabilities customer deposit and customer relationship	(1,828)	(2,402)
Deferred tax liabilities building valuation adjusment	(9,069)	(9,522)
Deferred Tax Liabilities Mortgage Servicing Rights	(3,830)	(3,844)
Deferred Tax Liabilities Other	(588)	(845)
Deferred Tax Liability Gross	(39,879)	(42,475)
Deferred Tax Assets Valuation Allowance	(3,135)	(3,133)
Deferred Tax Assets, Net	$ 127,421	$ 124,200