Collateral dependent impaired loans with specific reserves included in the allowance for loan losses.

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Collateral dependent impaired loans which had specific reserves.

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The percentage of liquidation expenses estimated with liquidating impaired collateral.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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Fair value of financial and nonfinancial obligations.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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Fair Value Measurements and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	$ 0	$ 0
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		0
Securities Available for Sale [Abstract]
Total Securities Available for Sale	1,288,899	1,288,899		$ 1,174,544
Trading Securities	8,852	$ 8,852		8,377
Liabilities [Abstract]
Decrease in goodwill	(1,200)
Minimum [Member]
Liabilities [Abstract]
Liquidation expense ratio on impaired collateral		10.00%
Maximum [Member]
Liabilities [Abstract]
Liquidation expense ratio on impaired collateral			35.00%
Federal Agency [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	256,093	$ 256,093		311,272
State & Municipal [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	38,654	38,654		31,637
Other Securities [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	20,318	20,318		16,768
Recurring Basis [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	1,288,899	1,288,899		1,174,544
Trading Securities	8,852	8,852		8,377
Interest Rate Swaps	18,977	18,977		6,224
Total	1,316,728	1,316,728		1,189,145
Liabilities [Abstract]
Interest Rate Swaps	18,258	18,258		6,224
Total	18,258	18,258		6,224
Recurring Basis [Member] \| Quoted Prices in Active Market for Identical Assets (Level I) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	10,964	10,964		7,526
Trading Securities	8,852	8,852		8,377
Interest Rate Swaps	0	0		0
Total	19,816	19,816		15,903
Liabilities [Abstract]
Interest Rate Swaps	0	0		0
Total	0	0		0
Recurring Basis [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	1,277,935	1,277,935		1,167,018
Trading Securities	0	0		0
Interest Rate Swaps	18,977	18,977		6,224
Total	1,296,912	1,296,912		1,173,242
Liabilities [Abstract]
Interest Rate Swaps	18,258	18,258		6,224
Total	18,258	18,258		6,224
Recurring Basis [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	0	0		0
Trading Securities	0	0		0
Interest Rate Swaps	0	0		0
Total	0	0		0
Liabilities [Abstract]
Interest Rate Swaps	0	0		0
Total	0	0		0
Recurring Basis [Member] \| Federal Agency [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	256,093	256,093		311,272
Recurring Basis [Member] \| Federal Agency [Member] \| Quoted Prices in Active Market for Identical Assets (Level I) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	0	0		0
Recurring Basis [Member] \| Federal Agency [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	256,093	256,093		311,272
Recurring Basis [Member] \| Federal Agency [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	0	0		0
Recurring Basis [Member] \| State & Municipal [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	38,654	38,654		31,637
Recurring Basis [Member] \| State & Municipal [Member] \| Quoted Prices in Active Market for Identical Assets (Level I) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	0	0		0
Recurring Basis [Member] \| State & Municipal [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	38,654	38,654		31,637
Recurring Basis [Member] \| State & Municipal [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	0	0		0
Recurring Basis [Member] \| Mortgage-Backed [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	372,364	372,364		409,896
Recurring Basis [Member] \| Mortgage-Backed [Member] \| Quoted Prices in Active Market for Identical Assets (Level I) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	0	0		0
Recurring Basis [Member] \| Mortgage-Backed [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	372,364	372,364		409,896
Recurring Basis [Member] \| Mortgage-Backed [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	0	0		0
Recurring Basis [Member] \| Collateralized Mortgage Obligations [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	601,470	601,470		404,971
Recurring Basis [Member] \| Collateralized Mortgage Obligations [Member] \| Quoted Prices in Active Market for Identical Assets (Level I) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	0	0		0
Recurring Basis [Member] \| Collateralized Mortgage Obligations [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	601,470	601,470		404,971
Recurring Basis [Member] \| Collateralized Mortgage Obligations [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	0	0		0
Recurring Basis [Member] \| Other Securities [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	20,318	20,318		16,768
Recurring Basis [Member] \| Other Securities [Member] \| Quoted Prices in Active Market for Identical Assets (Level I) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	10,964	10,964		7,526
Recurring Basis [Member] \| Other Securities [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	9,354	9,354		9,242
Recurring Basis [Member] \| Other Securities [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Securities Available for Sale [Abstract]
Total Securities Available for Sale	0	0		$ 0
Nonrecurring Basis [Member]
Liabilities [Abstract]
Collateral dependent impaired financing receivable with specific reserves	9,900	9,900	$ 9,900
Allowance for loan and lease losses collateral dependent impaired loans with specific reserves	$ 3,200	$ 3,200	$ 3,400