Commitments, Off-Balance Sheet Arrangements, Legal Proceedings and Regulatory Matters (Details Textuals) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Line Items]
Unfunded Commitments	$ 22,000		$ 22,000		$ 24,000
Expense Related to Qualified Affordable Housing Projects	5,000	$ 5,000	10,000	$ 9,000
Remaining Investment in Qualified Affordable Housing Projects	187,000		187,000		132,000
Variable Interest Entity Reporting Entity Involvement Unfunded Obligation Amount	95,000		95,000		51,000
Loans Repurchased Under Make Whole Requests	771		$ 771		$ 2,000
Loans Sold To Outside Investors Loss ReimbursementSettlement Paid			negligible		negligible
Loans Sold To Outside Investors Original Amount	11,600,000		$ 11,600,000
Loans Sold To Outside Investors Remaining Outstanding Amount	7,300,000		7,300,000
Residential Mortgage Loans Sold With Recourse Risk	34,000		34,000		$ 47,000
Residential Mortgage Loans Sold With Credit Recourse Risk	51,000		51,000		57,000
LendingRelatedCommitments, FairValue	0		0		0
UnconsolidatedProjectsLowIncomeHousing [Member]
Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Line Items]
Other Investments	196,000		196,000		136,000
PrincipalInvestmentCommitment [Member]
Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Line Items]
Other Investments	26,000		26,000		25,000
Standby Letters of Credit
Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Line Items]
Lines of Credit, Fair Value Disclosure	$ 3,000		$ 3,000		$ 2,000