Fair Value Measurements - Carrying Amounts and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Dec. 31, 2019
ASSETS
Cash and cash equivalents	$ 414,179	$ 65,387
Securities AFS, net	861,407	1,014,966
Loans held for sale	527,970	503,036
Loans, net	5,108,683	4,526,833
Investment in FHLB stock	23,598	21,519
Investment in equity securities	299	434
Liabilities:
Deposits	5,647,841	4,891,144
Borrowings	764,600	743,000
Assets Fair Value:
Cash and cash equivalents	414,179	65,387
Securities AFS, net	861,407	1,014,966
Loans held for sale	533,565	506,750
Loans, net	5,163,076	4,573,516
Investment in FHLB stock	23,598	21,519
Investment in equity securities	299	434
Liabilities Fair Value:
Deposits	5,657,313	4,891,145
Borrowings	764,600	743,000
Fair Value Measurement Level 1
ASSETS
Securities AFS, net	407	403
Investment in equity securities	299	434
Assets Fair Value:
Cash and cash equivalents	414,179	65,387
Securities AFS, net	407	403
Investment in equity securities	299	434
Liabilities Fair Value:
Deposits	3,825,306	2,913,493
Fair Value Measurement Level 2
ASSETS
Securities AFS, net	832,044	971,857
Investment in FHLB stock	23,598	21,519
Assets Fair Value:
Securities AFS, net	832,044	971,857
Loans held for sale	533,565	506,750
Investment in FHLB stock	23,598	21,519
Liabilities Fair Value:
Deposits	1,832,007	1,977,652
Borrowings	760,000	733,000
Fair Value Measurement Level 3
ASSETS
Securities AFS, net	28,956	42,706
Assets Fair Value:
Securities AFS, net	28,956	42,706
Loans, net	5,163,076	4,573,516
Liabilities Fair Value:
Borrowings	4,600	$ 10,000
Interest Rate Swaps
Liabilities:
Derivative liabilities	11,688
Liabilities Fair Value:
Derivative liabilities	11,688
Interest Rate Swaps \| Fair Value Measurement Level 2
Liabilities:
Derivative liabilities	11,688
Liabilities Fair Value:
Derivative liabilities	$ 11,688
Minimum \| Interest Rate Swaps
ASSETS
Duration of interest rate swap	1 year
Maximum \| Interest Rate Swaps
ASSETS
Duration of interest rate swap	30 years
Maximum \| LIBOR \| Interest Rate Swaps
ASSETS
Duration of interest rate swap	1 year

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Financing receivables held for sale value.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of short-term and long-term debt and lease obligation.

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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 investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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