Fair Value - Fair Value Measurements of Other Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Assets
Cash and due from banks	$ 211,189	$ 192,800
Interest-bearing deposits in other banks	78,069	153,770
Securities held-to-maturity	10,176	13,760
FHLB and FRB stock	80,302	69,708
Loans	11,344,564	10,342,083
Investment in BOLI	296,733	279,900
Liabilities
Deposits	12,084,112	11,053,325
Borrowed funds	906,079	714,884
Senior and subordinated debt	203,808	195,170
Level 1 \| Carrying Amount
Assets
Cash and due from banks	211,189	192,800
Level 1 \| Fair Value
Assets
Cash and due from banks	211,189	192,800
Level 2 \| Carrying Amount
Assets
Interest-bearing deposits in other banks	78,069	153,770
Securities held-to-maturity	10,176	13,760
FHLB and FRB stock	80,302	69,708
Liabilities
Deposits	12,084,112	11,053,325
Borrowed funds	906,079	714,884
Senior and subordinated debt	203,808	195,170
Accrued interest payable	10,005	4,704
Level 2 \| Fair Value
Assets
Interest-bearing deposits in other banks	78,069	153,770
Securities held-to-maturity	9,871	12,013
FHLB and FRB stock	80,302	69,708
Liabilities
Deposits	12,064,604	11,038,819
Borrowed funds	906,079	714,884
Senior and subordinated debt	211,207	208,666
Accrued interest payable	10,005	4,704
Level 3 \| Carrying Amount
Assets
Loans	11,346,668	10,345,397
Investment in BOLI	296,733	279,900
Accrued interest receivable	54,847	45,261
Other interest-earning assets	5	228
Level 3 \| Fair Value
Assets
Loans	11,052,040	10,059,992
Investment in BOLI	296,733	279,900
Accrued interest receivable	54,847	45,261
Other interest-earning assets	$ 5	$ 228

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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.

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums over and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans and leases covered under loss sharing agreements.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of interest earning assets classified as other.

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