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Fair Value Measurements (Assets Measured At Fair Value On A Recurring And Non-Recurring Basis) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	$ 34,697	$ 41,824
ATM and debit card	6,152	5,721	$ 5,687
Collateral Dependent Impaired Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	2,872
Loan Servicing Rights [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	1,022
Other Real Estate Owned [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	230
Level 1 Inputs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	12,229	15,211
Level 2 Inputs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	22,468	26,613
Measured On A Recurring Basis [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	446,308	524,973
Liabilities at fair value	1,139	23
Measured On A Recurring Basis [Member] | Derivative Instruments [Member] | Interest Rate Products [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value	2,006
Measured On A Recurring Basis [Member] | Derivative Instruments [Member] | Mortgage Banking [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value	27	3
Measured On A Recurring Basis [Member] | Derivative Instruments [Member] | Credit Contract [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value	24	4
Measured On A Recurring Basis [Member] | U.S. Government Agencies And Government Sponsored Enterprises [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	152,028	161,889
Measured On A Recurring Basis [Member] | Mortgage-Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	293,649	363,084
Measured On A Recurring Basis [Member] | Derivative Instruments, Assets [Member] | Cash Flow Hedging [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	631
Measured On A Recurring Basis [Member] | Derivative Instruments, Assets [Member] | Interest Rate Products [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	3,113
Measured On A Recurring Basis [Member] | Derivative Instruments, Assets [Member] | Mortgage Banking [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	83	30
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities
Liabilities at fair value
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member] | Derivative Instruments [Member] | Interest Rate Products [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member] | Derivative Instruments [Member] | Mortgage Banking [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member] | Derivative Instruments [Member] | Credit Contract [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member] | U.S. Government Agencies And Government Sponsored Enterprises [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member] | Mortgage-Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member] | Derivative Instruments, Assets [Member] | Cash Flow Hedging [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member] | Derivative Instruments, Assets [Member] | Interest Rate Products [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member] | Derivative Instruments, Assets [Member] | Mortgage Banking [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	446,308	524,973
Liabilities at fair value	1,139	23
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member] | Derivative Instruments [Member] | Interest Rate Products [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value	2,006
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member] | Derivative Instruments [Member] | Mortgage Banking [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value	27	3
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member] | Derivative Instruments [Member] | Credit Contract [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value	24	4
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member] | U.S. Government Agencies And Government Sponsored Enterprises [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	152,028	161,889
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member] | Mortgage-Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	293,649	363,084
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member] | Derivative Instruments, Assets [Member] | Cash Flow Hedging [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	631
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member] | Derivative Instruments, Assets [Member] | Interest Rate Products [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	3,113
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member] | Derivative Instruments, Assets [Member] | Mortgage Banking [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities	83	30
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities
Liabilities at fair value
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member] | Derivative Instruments [Member] | Interest Rate Products [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member] | Derivative Instruments [Member] | Mortgage Banking [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member] | Derivative Instruments [Member] | Credit Contract [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member] | U.S. Government Agencies And Government Sponsored Enterprises [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member] | Mortgage-Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member] | Derivative Instruments, Assets [Member] | Cash Flow Hedging [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member] | Derivative Instruments, Assets [Member] | Interest Rate Products [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member] | Derivative Instruments, Assets [Member] | Mortgage Banking [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities
Measured On A Nonrecurring Basis [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities at fair value	0	0
Assets at fair value	6,992	7,703
Measured On A Nonrecurring Basis [Member] | Loans Held For Sale [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	2,868	2,718
Measured On A Nonrecurring Basis [Member] | Collateral Dependent Impaired Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	2,872	3,847
Measured On A Nonrecurring Basis [Member] | Loan Servicing Rights [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	1,022	990
Measured On A Nonrecurring Basis [Member] | Other Real Estate Owned [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	230	148
Measured On A Nonrecurring Basis [Member] | Level 1 Inputs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 1 Inputs [Member] | Loans Held For Sale [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 1 Inputs [Member] | Collateral Dependent Impaired Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 1 Inputs [Member] | Loan Servicing Rights [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 1 Inputs [Member] | Other Real Estate Owned [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 2 Inputs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	2,868	2,718
Measured On A Nonrecurring Basis [Member] | Level 2 Inputs [Member] | Loans Held For Sale [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	2,868	2,718
Measured On A Nonrecurring Basis [Member] | Level 2 Inputs [Member] | Collateral Dependent Impaired Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 2 Inputs [Member] | Loan Servicing Rights [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 2 Inputs [Member] | Other Real Estate Owned [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 3 Inputs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	4,124	4,985
Measured On A Nonrecurring Basis [Member] | Level 3 Inputs [Member] | Loans Held For Sale [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 3 Inputs [Member] | Collateral Dependent Impaired Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	2,872	3,847
Measured On A Nonrecurring Basis [Member] | Level 3 Inputs [Member] | Loan Servicing Rights [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	1,022	990
Measured On A Nonrecurring Basis [Member] | Level 3 Inputs [Member] | Other Real Estate Owned [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets at fair value	$ 230	$ 148

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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