Fair Value (Details 1) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
Fair value measurement using significant unobservable input
Securities available-for-sale	$ 785,693	$ 785,693	$ 814,931
Reconciliation and income statement classification of gains and losses for all assets measured at fair value on a recurring basis using significant unobservable inputs
Beginning balance	6,585	18,285	16,578
Total realized/unrealized gains or losses - Included in earnings	0	0	0
Total realized/unrealized gains or losses - Included in other comprehensive income	13	4,158	2,773
Transfers	0	0
Purchases			0
Settlements	(40)	(15,885)	(1,066)
Ending balance	6,558	6,558	18,285
US Government Agencies Debt Securities [Member]
Fair value measurement using significant unobservable input
Securities available-for-sale	12,473	12,473	13,695
State and Municipal Obligations
Fair value measurement using significant unobservable input
Securities available-for-sale	230,599	230,599	231,622
Reconciliation and income statement classification of gains and losses for all assets measured at fair value on a recurring basis using significant unobservable inputs
Beginning balance	3,135	3,680	4,210
Total realized/unrealized gains or losses - Included in earnings	0	0	0
Total realized/unrealized gains or losses - Included in other comprehensive income	0	0	0
Transfers	0	0
Purchases			0
Settlements	0	(545)	(530)
Ending balance	3,135	3,135	3,680
Collateralized Debt Obligations
Fair value measurement using significant unobservable input
Securities available-for-sale	3,423	3,423	14,605
Reconciliation and income statement classification of gains and losses for all assets measured at fair value on a recurring basis using significant unobservable inputs
Beginning balance	3,450	14,605	12,368
Total realized/unrealized gains or losses - Included in earnings	0	0	0
Total realized/unrealized gains or losses - Included in other comprehensive income	13	4,158	2,773
Transfers	0	0
Purchases			0
Settlements	(40)	(15,340)	(536)
Ending balance	3,423	3,423	14,605
Mortgage Backed Securities - Residential
Fair value measurement using significant unobservable input
Securities available-for-sale	184,651	184,651	215,338
Mortgage Backed Securities - Commercial
Fair value measurement using significant unobservable input
Securities available-for-sale			1
Collateralized Mortgage Obligations
Fair value measurement using significant unobservable input
Securities available-for-sale	354,547	354,547	339,670
Fair Value, Inputs, Level 3 [Member]
Fair value measurement using significant unobservable input
Securities available-for-sale	6,558	6,558	18,285
Fair Value, Inputs, Level 3 [Member] \| US Government Agencies Debt Securities [Member]
Fair value measurement using significant unobservable input
Securities available-for-sale	0	0	0
Fair Value, Inputs, Level 3 [Member] \| State and Municipal Obligations
Fair value measurement using significant unobservable input
Securities available-for-sale	3,135	3,135	3,680
Fair Value, Inputs, Level 3 [Member] \| Collateralized Debt Obligations
Fair value measurement using significant unobservable input
Securities available-for-sale	3,423	3,423	14,605
Fair Value, Inputs, Level 3 [Member] \| Mortgage Backed Securities - Residential
Fair value measurement using significant unobservable input
Securities available-for-sale	0	0	0
Fair Value, Inputs, Level 3 [Member] \| Mortgage Backed Securities - Commercial
Fair value measurement using significant unobservable input
Securities available-for-sale			0
Fair Value, Inputs, Level 3 [Member] \| Collateralized Mortgage Obligations
Fair value measurement using significant unobservable input
Securities available-for-sale	0	0	0
Fair Value, Inputs, Level 1 [Member]
Fair value measurement using significant unobservable input
Securities available-for-sale	0	0	0
Fair Value, Inputs, Level 1 [Member] \| US Government Agencies Debt Securities [Member]
Fair value measurement using significant unobservable input
Securities available-for-sale	0	0	0
Fair Value, Inputs, Level 1 [Member] \| State and Municipal Obligations
Fair value measurement using significant unobservable input
Securities available-for-sale	0	0	0
Fair Value, Inputs, Level 1 [Member] \| Collateralized Debt Obligations
Fair value measurement using significant unobservable input
Securities available-for-sale	0	0	0
Fair Value, Inputs, Level 1 [Member] \| Mortgage Backed Securities - Residential
Fair value measurement using significant unobservable input
Securities available-for-sale	0	0	0
Fair Value, Inputs, Level 1 [Member] \| Mortgage Backed Securities - Commercial
Fair value measurement using significant unobservable input
Securities available-for-sale			0
Fair Value, Inputs, Level 1 [Member] \| Collateralized Mortgage Obligations
Fair value measurement using significant unobservable input
Securities available-for-sale	0	0	0
Fair Value, Inputs, Level 2 [Member]
Fair value measurement using significant unobservable input
Securities available-for-sale	779,135	779,135	796,646
Reconciliation and income statement classification of gains and losses for all assets measured at fair value on a recurring basis using significant unobservable inputs
Derivative Assets	687	687	298
Derivative Liability	687	687	298
Fair Value, Inputs, Level 2 [Member] \| US Government Agencies Debt Securities [Member]
Fair value measurement using significant unobservable input
Securities available-for-sale	12,473	12,473	13,695
Fair Value, Inputs, Level 2 [Member] \| State and Municipal Obligations
Fair value measurement using significant unobservable input
Securities available-for-sale	227,464	227,464	227,942
Fair Value, Inputs, Level 2 [Member] \| Collateralized Debt Obligations
Fair value measurement using significant unobservable input
Securities available-for-sale	0	0	0
Fair Value, Inputs, Level 2 [Member] \| Mortgage Backed Securities - Residential
Fair value measurement using significant unobservable input
Securities available-for-sale	184,651	184,651	215,338
Fair Value, Inputs, Level 2 [Member] \| Mortgage Backed Securities - Commercial
Fair value measurement using significant unobservable input
Securities available-for-sale			1
Fair Value, Inputs, Level 2 [Member] \| Collateralized Mortgage Obligations
Fair value measurement using significant unobservable input
Securities available-for-sale	$ 354,547	$ 354,547	$ 339,670

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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