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Fair value disclosure only table (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Assets, Fair Value Disclosure [Abstract] |  |
Debt Securities, Held-to-maturity | $ 740,806 | $ 611,490
Loans and Leases Receivable, Net Amount | 8,805,899 | 6,841,901
Securities held to maturity, fair value | 753,263 | 603,640
Federal Home Loan Bank Stock | 14,424 | 15,683
Bank Owned Life Insurance | 197,372 | 160,456
Liabilities, Fair Value Disclosure [Abstract] |  |
Advances from Federal Home Loan Banks | 115,748 | 147,806
Junior subordinated debentures (less unamortized debt issuance costs of $40 and $118) | 62,848 | 76,173
Subordinated Debt | 49,601 | 34,728
Long-term Debt | 74,906 | 0
Long-term Debt, Fair Value | 72,219 |
Deposits [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Financial Liabilities Book Value | 7,752,052 | 6,716,017
Accrued Liabilities, Fair Value Disclosure | 7,752,052 | 6,716,017
Bank Time Deposits [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Financial Liabilities Book Value | 1,395,315 | 711,103
Accrued Liabilities, Fair Value Disclosure | 1,396,760 | 703,728
Federal Home Loan Bank Advances [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Advances from Federal Home Loan Banks | 115,748 | 147,806
Federal Home Loan Bank Borrowings, Fair Value Disclosure | 115,881 | 147,603
Junior Subordinated Debt [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Junior subordinated debentures (less unamortized debt issuance costs of $40 and $118) | 62,848 | 76,173
Accrued Liabilities, Fair Value Disclosure | 65,603 | 73,827
Subordinated Debt [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Subordinated Debt | 49,601 | 34,728
Accrued Liabilities, Fair Value Disclosure | 52,870 | 32,509
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Long-term Debt [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Long-term Debt, Fair Value | 0 |
Significant Other Observable Inputs (Level 2) [Member] | Deposits [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Accrued Liabilities, Fair Value Disclosure | 7,752,052 | 6,716,017
Significant Other Observable Inputs (Level 2) [Member] | Bank Time Deposits [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Accrued Liabilities, Fair Value Disclosure | 1,396,760 | 703,728
Significant Other Observable Inputs (Level 2) [Member] | Federal Home Loan Bank Advances [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Federal Home Loan Bank Borrowings, Fair Value Disclosure | 115,881 |
Accrued Liabilities, Fair Value Disclosure |  | 147,603
Significant Other Observable Inputs (Level 2) [Member] | Junior Subordinated Debt [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Accrued Liabilities, Fair Value Disclosure | 65,603 | 73,827
Significant Other Observable Inputs (Level 2) [Member] | Long-term Debt [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Long-term Debt, Fair Value | 72,219 |
Significant Unobservable Inputs (Level 3) [Member] | Subordinated Debt [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Accrued Liabilities, Fair Value Disclosure | 52,870 | 32,509
Significant Unobservable Inputs (Level 3) [Member] | Long-term Debt [Member] |  |
Liabilities, Fair Value Disclosure [Abstract] |  |
Long-term Debt, Fair Value | 0 |
US Government Agencies Debt Securities [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Debt Securities, Held-to-maturity | 12,874 |
Securities held to maturity, fair value | 12,997 |
US Government Agencies Debt Securities [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Securities held to maturity, fair value | 12,997 |
US Treasury Securities [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Debt Securities, Held-to-maturity | 4,032 | 1,004
Securities held to maturity, fair value | 4,053 | 1,015
US Treasury Securities [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Securities held to maturity, fair value | 4,053 | 1,015
Agency mortgage-backed securities |  |
Assets, Fair Value Disclosure [Abstract] |  |
Debt Securities, Held-to-maturity | 397,414 | 252,484
Securities held to maturity, fair value | 405,802 | 250,928
Agency mortgage-backed securities | Significant Other Observable Inputs (Level 2) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Securities held to maturity, fair value | 405,802 | 250,928
Agency collateralized mortgage obligations |  |
Assets, Fair Value Disclosure [Abstract] |  |
Debt Securities, Held-to-maturity | 293,662 | 332,775
Securities held to maturity, fair value | 297,314 | 326,724
Agency collateralized mortgage obligations | Significant Other Observable Inputs (Level 2) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Securities held to maturity, fair value | 297,314 | 326,724
Single issuer trust preferred securities issued by banks and insurers |  |
Assets, Fair Value Disclosure [Abstract] |  |
Debt Securities, Held-to-maturity | 1,500 | 1,500
Securities held to maturity, fair value | 1,490 | 1,490
Single issuer trust preferred securities issued by banks and insurers | Significant Other Observable Inputs (Level 2) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Securities held to maturity, fair value | 1,490 | 1,490
Small Business Administration Pooled Securities [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Debt Securities, Held-to-maturity | 31,324 | 23,727
Securities held to maturity, fair value | 31,607 | 23,483
Small Business Administration Pooled Securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Securities held to maturity, fair value | 0 | 0
Small Business Administration Pooled Securities [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Securities held to maturity, fair value | 31,607 | 23,483
Small Business Administration Pooled Securities [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Securities held to maturity, fair value | 0 | 0
Loans Net Of Allowance For Loan Loses [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Loans and Leases Receivable, Net Amount | 8,780,384 | 6,812,792
Loans, net of allowance for loan losses | 8,613,635 | 6,635,209
Loans Net Of Allowance For Loan Loses [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Loans, net of allowance for loan losses | 8,613,635 | 6,635,209
Investment in Federal Home Loan Bank Stock [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Federal Home Loan Bank Stock | 14,424 | 15,683
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure | 14,424 | 15,683
Investment in Federal Home Loan Bank Stock [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure | 0 | 0
Investment in Federal Home Loan Bank Stock [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure | 14,424 | 15,683
Investment in Federal Home Loan Bank Stock [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure | 0 | 0
Cash Surrender Value [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Bank Owned Life Insurance | 197,372 | 160,456
Cash Surrender Value, Fair Value Disclosure | 197,372 | 160,456
Cash Surrender Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Cash Surrender Value, Fair Value Disclosure | 0 | 0
Cash Surrender Value [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Cash Surrender Value, Fair Value Disclosure | 197,372 | 160,456
Cash Surrender Value [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Assets, Fair Value Disclosure [Abstract] |  |
Cash Surrender Value, Fair Value Disclosure | $ 0 | $ 0

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- Definition Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 + Details
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- Definition The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + 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://fasb.org/us-gaap/role/ref/legacyRef -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=119400593&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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