Allowance for Loan Losses - Activity in Allowance for Losses Disaggregated on Basis of Impairment (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	$ 1,597,000
Impaired Financing Receivable, Recorded Investment				$ 57,481,000
Schedule of allowance for loan losses on the basis of impairment method
Loans Individually Evaluated for Impairment				2,143,000
Loans Collectively Evaluated for Impairment				31,759,000
PCI Loans				2,269,000
Total Allowance for Credit Losses		$ 36,152,000	$ 37,993,000	36,171,000	$ 35,042,000
Financing Receivable, Allowance for Credit Loss, Recovery	1,180,000
Financing Receivable, Allowance for Credit Loss, Writeoff Net	(417,000)
Allowance for Loan and Lease Losses, Write-offs		704,000
Allowance for Loan and Lease Loss, Recovery of Bad Debts		894,000
Provision for credit losses	$ 9,964,000	920,000
Provision for Loan and Lease Losses, Increase (Decrease), Percentage	26.20%
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	$ 1,222,000
Impaired Financing Receivable, Recorded Investment				56,468,000
Schedule of allowance for loan losses on the basis of impairment method
Loans Individually Evaluated for Impairment				1,944,000
Loans Collectively Evaluated for Impairment				20,394,000
PCI Loans				1,595,000
Total Allowance for Credit Losses		24,836,000	20,998,000	23,933,000	23,711,000
Financing Receivable, Allowance for Credit Loss, Recovery	1,069,000
Allowance for Loan and Lease Losses, Write-offs		103,000
Allowance for Loan and Lease Loss, Recovery of Bad Debts		159,000
Provision for credit losses	7,021,000	1,069,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	1,087,000
Impaired Financing Receivable, Recorded Investment				43,808,000
Schedule of allowance for loan losses on the basis of impairment method
Loans Individually Evaluated for Impairment				1,372,000
Loans Collectively Evaluated for Impairment				9,772,000
PCI Loans				595,000
Total Allowance for Credit Losses		11,755,000	10,391,000	11,739,000	11,343,000
Financing Receivable, Allowance for Credit Loss, Recovery	1,057,000
Allowance for Loan and Lease Losses, Write-offs		103,000
Allowance for Loan and Lease Loss, Recovery of Bad Debts		7,000
Provision for credit losses	3,539,000	508,000
Commercial Portfolio Segment [Member] | Owner Occupied Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	135,000
Impaired Financing Receivable, Recorded Investment				6,336,000
Schedule of allowance for loan losses on the basis of impairment method
Loans Individually Evaluated for Impairment				426,000
Loans Collectively Evaluated for Impairment				3,558,000
PCI Loans				528,000
Total Allowance for Credit Losses		5,256,000	4,964,000	4,512,000	4,898,000
Financing Receivable, Allowance for Credit Loss, Recovery	12,000
Allowance for Loan and Lease Losses, Write-offs		0
Allowance for Loan and Lease Loss, Recovery of Bad Debts		3,000
Provision for credit losses	1,375,000	355,000
Commercial Portfolio Segment [Member] | Non Owner Occupied Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	0
Impaired Financing Receivable, Recorded Investment				6,324,000
Schedule of allowance for loan losses on the basis of impairment method
Loans Individually Evaluated for Impairment				146,000
Loans Collectively Evaluated for Impairment				7,064,000
PCI Loans				472,000
Total Allowance for Credit Losses		7,825,000	5,643,000	7,682,000	7,470,000
Financing Receivable, Allowance for Credit Loss, Recovery	0
Allowance for Loan and Lease Losses, Write-offs		0
Allowance for Loan and Lease Loss, Recovery of Bad Debts		149,000
Provision for credit losses	2,107,000	206,000
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	0
Impaired Financing Receivable, Recorded Investment				215,000
Schedule of allowance for loan losses on the basis of impairment method
Loans Individually Evaluated for Impairment				56,000
Loans Collectively Evaluated for Impairment				1,316,000
PCI Loans				86,000
Total Allowance for Credit Losses		1,247,000	2,929,000	1,458,000	1,203,000
Financing Receivable, Allowance for Credit Loss, Recovery	3,000
Allowance for Loan and Lease Losses, Write-offs		15,000
Allowance for Loan and Lease Loss, Recovery of Bad Debts		0
Provision for credit losses	94,000	59,000
Real Estate Construction and Land Development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	0
Schedule of allowance for loan losses on the basis of impairment method
Loans Individually Evaluated for Impairment				0
Loans Collectively Evaluated for Impairment				2,823,000
PCI Loans				237,000
Total Allowance for Credit Losses		2,417,000	9,729,000	3,060,000	2,194,000
Financing Receivable, Allowance for Credit Loss, Recovery	14,000
Allowance for Loan and Lease Losses, Write-offs		0
Allowance for Loan and Lease Loss, Recovery of Bad Debts		618,000
Provision for credit losses	2,565,000	(395,000)
Real Estate Construction and Land Development | One-to-four Family Real Estate Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	0
Impaired Financing Receivable, Recorded Investment				237,000
Schedule of allowance for loan losses on the basis of impairment method
Loans Individually Evaluated for Impairment				0
Loans Collectively Evaluated for Impairment				1,296,000
PCI Loans				159,000
Total Allowance for Credit Losses		1,422,000	884,000	1,455,000	1,240,000
Financing Receivable, Allowance for Credit Loss, Recovery	14,000
Allowance for Loan and Lease Losses, Write-offs		0
Allowance for Loan and Lease Loss, Recovery of Bad Debts		618,000
Provision for credit losses	(34,000)	(436,000)
Real Estate Construction and Land Development | Five or More Family Residential and Commercial Properties [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	0
Schedule of allowance for loan losses on the basis of impairment method
Loans Individually Evaluated for Impairment				0
Loans Collectively Evaluated for Impairment				1,527,000
PCI Loans				78,000
Total Allowance for Credit Losses		995,000	8,845,000	1,605,000	954,000
Financing Receivable, Allowance for Credit Loss, Recovery	0
Allowance for Loan and Lease Losses, Write-offs		0
Allowance for Loan and Lease Loss, Recovery of Bad Debts		0
Provision for credit losses	2,599,000	41,000
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	375,000
Impaired Financing Receivable, Recorded Investment				561,000
Schedule of allowance for loan losses on the basis of impairment method
Loans Individually Evaluated for Impairment				143,000
Loans Collectively Evaluated for Impairment				6,327,000
PCI Loans				351,000
Total Allowance for Credit Losses		6,480,000	4,337,000	6,821,000	6,581,000
Financing Receivable, Allowance for Credit Loss, Recovery	94,000
Allowance for Loan and Lease Losses, Write-offs		586,000
Allowance for Loan and Lease Loss, Recovery of Bad Debts		117,000
Provision for credit losses	284,000	368,000
Unallocated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	0
Schedule of allowance for loan losses on the basis of impairment method
Loans Individually Evaluated for Impairment				0
Loans Collectively Evaluated for Impairment				899,000
PCI Loans				0
Total Allowance for Credit Losses		1,172,000	$ 0	$ 899,000	$ 1,353,000
Financing Receivable, Allowance for Credit Loss, Recovery	0
Allowance for Loan and Lease Losses, Write-offs		0
Allowance for Loan and Lease Loss, Recovery of Bad Debts		0
Provision for credit losses	$ 0	$ (181,000)