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

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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 of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance and after 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.

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Loans Receivable - Loan Origination/Risk Management (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($) segment	Jan. 01, 2020 USD ($)	Dec. 31, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest receivable	$ 14,940		$ 14,446
Number of loan segments \| segment	4
Loans receivable	$ 3,852,376		3,767,879
Financing Receivable, Allowance for Credit Loss	47,540
Loans and Leases Receivable, Allowance		$ 37,993	36,171	$ 36,152	$ 35,042
Loans and Leases Receivable, Net Amount	3,804,836		3,731,708
Loans Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest receivable	11,100		10,700
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	3,007,629		2,946,233
Financing Receivable, Allowance for Credit Loss	27,866
Loans and Leases Receivable, Allowance		20,998	23,933	24,836	23,711
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	889,685		852,220
Financing Receivable, Allowance for Credit Loss	13,900
Loans and Leases Receivable, Allowance		10,391	11,739	11,755	11,343
Commercial Portfolio Segment [Member] \| Owner Occupied Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	805,636		805,234
Financing Receivable, Allowance for Credit Loss	6,216
Loans and Leases Receivable, Allowance		4,964	4,512	5,256	4,898
Commercial Portfolio Segment [Member] \| Non Owner Occupied Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,312,308		1,288,779
Financing Receivable, Allowance for Credit Loss	7,750
Loans and Leases Receivable, Allowance		5,643	7,682	7,825	7,470
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	136,782		131,660
Financing Receivable, Allowance for Credit Loss	3,026
Loans and Leases Receivable, Allowance		2,929	1,458	1,247	1,203
Real Estate Construction and Land Development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	287,034		274,646
Financing Receivable, Allowance for Credit Loss	12,308
Loans and Leases Receivable, Allowance		9,729	3,060	2,417	2,194
Real Estate Construction and Land Development \| One-to-four Family Real Estate Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	98,730		104,296
Financing Receivable, Allowance for Credit Loss	864
Loans and Leases Receivable, Allowance		884	1,455	1,422	1,240
Real Estate Construction and Land Development \| Five or More Family Residential and Commercial Properties [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	188,304		170,350
Financing Receivable, Allowance for Credit Loss	11,444
Loans and Leases Receivable, Allowance		8,845	1,605	995	954
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	420,931		415,340
Financing Receivable, Allowance for Credit Loss	$ 4,340
Loans and Leases Receivable, Allowance		$ 4,337	$ 6,821	$ 6,480	$ 6,581