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Fair Value Measurements and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands | Jun. 30, 2016 | Dec. 31, 2015 | Jun. 30, 2015
--- | --- | --- | ---
Securities Available for Sale [Abstract] |  |  |
Total Securities Available for Sale | $ 1,271,596 | $ 1,174,544 |
Trading Securities | $ 8,591 | 8,377 |
Liabilities [Abstract] |  |  |
Liquidation expense ratio on impaired collateral minimum | 10.00% |  |
Liquidation expense ratio on impaired collateral maximum | 35.00% |  |
Financial assets [Abstract] |  |  |
Securities held to maturity | $ 512,349 | 473,140 |
Financial liabilities [Abstract] |  |  |
Time deposits | 882,712 | 908,827 |
Long-term debt | 110,306 | 130,447 |
Junior subordinated debt | 101,196 | 101,196 |
Not Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member] | Other Assets [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Fair value of derivative asset | 17,800 | 6,200 |
Not Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member] | Other Liabilities [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Fair value of derivative liability | 17,800 | 6,200 |
Not Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member] | Customer Derivative Agreement [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Notional amount | 288,100 | 192,600 |
Not Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member] | Offsetting Derivative Counterparty Positions [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Notional amount | 288,100 | 192,600 |
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Interest Rate Swaps [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Notional amount | 150,000 |  |
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Interest Rate Swaps [Member] | Other Liabilities [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Fair value of derivative liability | 100 |  |
Carrying Amount [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |
Financial assets [Abstract] |  |  |
Securities held to maturity | 500,840 | 471,031 |
Financial liabilities [Abstract] |  |  |
Time deposits | 882,712 | 908,827 |
Long-term debt | 110,306 | 130,447 |
Junior subordinated debt | 101,196 | 101,196 |
Carrying Amount [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |
Financial assets [Abstract] |  |  |
Net loans | 5,974,825 | 5,820,115 |
Estimated Fair Value [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |
Financial assets [Abstract] |  |  |
Securities held to maturity | 512,349 | 473,140 |
Financial liabilities [Abstract] |  |  |
Time deposits | 886,047 | 903,501 |
Long-term debt | 111,968 | 131,268 |
Junior subordinated debt | 96,583 | 97,346 |
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |
Financial assets [Abstract] |  |  |
Net loans | 6,136,103 | 5,958,427 |
Recurring Basis [Member] |  |  |
Securities Available for Sale [Abstract] |  |  |
Federal Agency | 266,835 | 311,272 |
State & municipal | 37,630 | 31,637 |
Mortgage-backed | 396,685 | 409,896 |
Collateralized mortgage obligations | 551,638 | 404,971 |
Other securities | 18,808 | 16,768 |
Total Securities Available for Sale | 1,271,596 | 1,174,544 |
Trading Securities | 8,591 | 8,377 |
Interest Rate Swaps | 17,775 | 6,224 |
Total | 1,297,962 | 1,189,145 |
Liabilities [Abstract] |  |  |
Interest Rate Swaps | 17,838 | 6,224 |
Total | 17,838 | 6,224 |
Recurring Basis [Member] | Quoted Prices in Active Market for Identical Assets (Level I) [Member] |  |  |
Securities Available for Sale [Abstract] |  |  |
Federal Agency | 0 | 0 |
State & municipal | 0 | 0 |
Mortgage-backed | 0 | 0 |
Collateralized mortgage obligations | 0 | 0 |
Other securities | 9,458 | 7,526 |
Total Securities Available for Sale | 9,458 | 7,526 |
Trading Securities | 8,591 | 8,377 |
Interest Rate Swaps | 0 | 0 |
Total | 18,049 | 15,903 |
Liabilities [Abstract] |  |  |
Interest Rate Swaps | 0 | 0 |
Total | 0 | 0 |
Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |
Securities Available for Sale [Abstract] |  |  |
Federal Agency | 266,835 | 311,272 |
State & municipal | 37,630 | 31,637 |
Mortgage-backed | 396,685 | 409,896 |
Collateralized mortgage obligations | 551,638 | 404,971 |
Other securities | 9,350 | 9,242 |
Total Securities Available for Sale | 1,262,138 | 1,167,018 |
Trading Securities | 0 | 0 |
Interest Rate Swaps | 17,775 | 6,224 |
Total | 1,279,913 | 1,173,242 |
Liabilities [Abstract] |  |  |
Interest Rate Swaps | 17,838 | 6,224 |
Total | 17,838 | 6,224 |
Recurring Basis [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |
Securities Available for Sale [Abstract] |  |  |
Federal Agency | 0 | 0 |
State & municipal | 0 | 0 |
Mortgage-backed | 0 | 0 |
Collateralized mortgage obligations | 0 | 0 |
Other securities | 0 | 0 |
Total Securities Available for Sale | 0 | 0 |
Trading Securities | 0 | 0 |
Interest Rate Swaps | 0 | 0 |
Total | 0 | 0 |
Liabilities [Abstract] |  |  |
Interest Rate Swaps | 0 | 0 |
Total | 0 | $ 0 |
Nonrecurring Basis [Member] |  |  |
Liabilities [Abstract] |  |  |
Collateral dependent impaired financing receivable with specific reserves | 9,600 |  | $ 8,700
Allowance for loan and lease losses collateral dependent impaired loans with specific reserves | $ 3,200 |  | $ 2,900

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- Definition Represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Element may be used with the fair value disclosures required in the footnote disclosures to the financial statements, and used in the balance sheet and disclosure in the same submission. Represents other securities categorized as available-for-sale. + References No definition available. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents investments in US Agency securities. + References No definition available. + Details
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- Definition Fair value of investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 + Details
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- Definition Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 + Details
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- Definition Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Mortgage-Backed Securities -URI http://asc.fasb.org/extlink&oid=6517959 + Details
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