Disclosures about Fair Value of Financial Instruments - Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Financial Assets
Available-for-sale securities	$ 697,847	$ 739,473
Restricted equity securities	20,675	17,278
Derivative assets	29,302	9,838
Financial Liabilities
Derivative liabilities	29,432	9,907
Carrying Amount
Financial Assets
Cash and cash equivalents	194,371	187,320
Available-for-sale securities	700,083	741,634
Loans, net of allowance for loan losses	4,342,039	3,795,348
Restricted equity securities	20,675	17,278
Interest receivable	19,399	15,716
Derivative assets	29,302	9,838
Total financial assets	5,305,869	4,767,134
Financial Liabilities
Deposits	4,304,143	3,923,759
Federal funds purchased and repurchase agreements	49,881	14,921
Federal Home Loan Bank advances	450,617	358,743
Other borrowings	942	921
Interest payable	2,843	4,584
Derivative liabilities	29,432	9,907
Total financial liabilities	4,837,858	4,312,835
Estimate of Fair Value Measurement
Financial Assets
Cash and cash equivalents	194,371	187,320
Available-for-sale securities	700,083	741,634
Loans, net of allowance for loan losses	4,334,224	3,810,818
Restricted equity securities	20,675	17,278
Interest receivable	19,399	15,716
Derivative assets	29,302	9,838
Total financial assets	5,298,054	4,782,604
Financial Liabilities
Deposits	4,349,570	3,928,838
Federal funds purchased and repurchase agreements	49,881	14,921
Federal Home Loan Bank advances	468,650	357,859
Other borrowings	1,722	2,147
Interest payable	2,843	4,584
Derivative liabilities	29,432	9,907
Total financial liabilities	4,902,098	4,318,256
Estimate of Fair Value Measurement | Level 1
Financial Assets
Cash and cash equivalents	194,371	187,320
Available-for-sale securities	0	0
Loans, net of allowance for loan losses	0	0
Restricted equity securities	0	0
Interest receivable	0	0
Derivative assets	0	0
Total financial assets	194,371	187,320
Financial Liabilities
Deposits	750,333	521,826
Federal funds purchased and repurchase agreements	0	0
Federal Home Loan Bank advances	0	0
Other borrowings	0	0
Interest payable	0	0
Derivative liabilities	0	0
Total financial liabilities	750,333	521,826
Estimate of Fair Value Measurement | Level 2
Financial Assets
Cash and cash equivalents	0	0
Available-for-sale securities	700,083	741,634
Loans, net of allowance for loan losses	0	0
Restricted equity securities	0	0
Interest receivable	19,399	15,716
Derivative assets	29,302	9,838
Total financial assets	748,784	767,188
Financial Liabilities
Deposits	0	0
Federal funds purchased and repurchase agreements	49,881	14,921
Federal Home Loan Bank advances	468,650	357,859
Other borrowings	1,722	2,147
Interest payable	2,843	4,584
Derivative liabilities	29,432	9,907
Total financial liabilities	552,528	389,418
Estimate of Fair Value Measurement | Level 3
Financial Assets
Cash and cash equivalents	0	0
Available-for-sale securities	0	0
Loans, net of allowance for loan losses	4,334,224	3,810,818
Restricted equity securities	20,675	17,278
Interest receivable	0	0
Derivative assets	0	0
Total financial assets	4,354,899	3,828,096
Financial Liabilities
Deposits	3,599,237	3,407,012
Federal funds purchased and repurchase agreements	0	0
Federal Home Loan Bank advances	0	0
Other borrowings	0	0
Interest payable	0	0
Derivative liabilities	0	0
Total financial liabilities	$ 3,599,237	$ 3,407,012