Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS (Details) - TDRs By Class - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		$ 2,112	$ 2,291
Non-accrual	[1]	3,112	6,297
Total		5,224	8,588	$ 4,970
Commercial, industrial, and agricultural | Commercial and industrial
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		278	281
Non-accrual	[1]	922	150
Total		1,200	431
Commercial, industrial, and agricultural | Agricultural
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		0	0
Non-accrual	[1]	0	0
Total		0	0
Commercial real estate loans
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		845	1,009
Non-accrual	[1]	1,027	4,949
Total		1,872	5,958
Commercial real estate loans | Office, retail, and industrial
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		0	155
Non-accrual	[1]	864	4,733
Total		864	4,888
Commercial real estate loans | Multi-family
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		582	586
Non-accrual	[1]	163	168
Total		745	754
Commercial real estate loans | Construction
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		0	0
Non-accrual	[1]	0	0
Total		0	0
Commercial real estate loans | Other commercial real estate
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		263	268
Non-accrual	[1]	0	48
Total		263	316
Total corporate loans
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		1,123	1,290
Non-accrual	[1]	1,949	5,099
Total		3,072	6,389
Consumer loans
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		989	1,001
Non-accrual	[1]	1,163	1,198
Total		2,152	2,199
Consumer loans | Home equity
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		172	177
Non-accrual	[1]	795	820
Total		967	997
Consumer loans | 1-4 family mortgages
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		817	824
Non-accrual	[1]	368	378
Total		1,185	1,202
Consumer loans | Installment
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		0	0
Non-accrual	[1]	0	0
Total		$ 0	$ 0

[1] These TDRs are included in non-accrual loans in the preceding tables.