Disclosures of Fair Values of Financial Instruments - Summary of Estimated Fair Values of Company Financial Instruments (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Financial Assets
Total available-for-sale securities	$ 879,240,000	$ 685,636,000
Held-to-maturity securities	5,119,000	69,572,000
Equity securities, at fair value	218,000	412,000
Fair Value, Inputs, Level 1 [Member]
Financial Assets
Cash and due from banks	415,973,000	84,154,000
Federal funds sold	1,308,000	926,000
Certificates of deposit investments	0	0
Total available-for-sale securities	0	0
Held-to-maturity securities	0	0
Equity securities, at fair value	218,000	219,000
Loans held for sale	0	0
Loans net of allowance for credit losses	0	0
Interest receivable	0	0
Federal Reserve Bank stock	0	0
Federal Home Loan Bank stock	0	0
Financial Liabilities
Deposits	0	0
Securities sold under agreements to repurchase	0	0
Interest payable	0	0
Federal Home Loan Bank borrowings	0	0
Other borrowings	0	5,000,000
Fair Value, Inputs, Level 1 [Member] \| Subordinated Debt
Financial Liabilities
Subordinated debentures	0
Fair Value, Inputs, Level 1 [Member] \| Junior Subordinated Debentures
Financial Liabilities
Subordinated debentures	0	0
Fair Value, Inputs, Level 2 [Member]
Financial Assets
Cash and due from banks	0	0
Federal funds sold	0	0
Certificates of deposit investments	2,695,000	4,625,000
Total available-for-sale securities	878,446,000	684,856,000
Held-to-maturity securities	5,119,000	69,572,000
Equity securities, at fair value	0	0
Loans held for sale	1,924,000	1,820,000
Loans net of allowance for credit losses	0	0
Interest receivable	19,287,000	15,577,000
Federal Reserve Bank stock	9,401,000	9,401,000
Federal Home Loan Bank stock	5,450,000	4,105,000
Financial Liabilities
Deposits	3,215,715,000	2,332,866,000
Securities sold under agreements to repurchase	206,945,000	208,016,000
Interest payable	2,345,000	2,261,000
Federal Home Loan Bank borrowings	96,669,000	114,510,000
Other borrowings	0	0
Fair Value, Inputs, Level 2 [Member] \| Subordinated Debt
Financial Liabilities
Subordinated debentures	94,253,000
Fair Value, Inputs, Level 2 [Member] \| Junior Subordinated Debentures
Financial Liabilities
Subordinated debentures	14,604,000	15,596,000
Level 3
Financial Assets
Cash and due from banks	0	0
Federal funds sold	0	0
Certificates of deposit investments	0	0
Total available-for-sale securities	794,000	780,000
Held-to-maturity securities	0	0
Equity securities, at fair value	0	193,000
Loans held for sale	0	0
Loans net of allowance for credit losses	3,056,344,000	2,622,053,000
Interest receivable	0	0
Federal Reserve Bank stock	0	0
Federal Home Loan Bank stock	0	0
Financial Liabilities
Deposits	481,390,000	591,278,000
Securities sold under agreements to repurchase	0	0
Interest payable	0	0
Federal Home Loan Bank borrowings	0	0
Other borrowings	0	0
Level 3 \| Subordinated Debt
Financial Liabilities
Subordinated debentures	0
Level 3 \| Junior Subordinated Debentures
Financial Liabilities
Subordinated debentures	0	0
Carrying Amount
Financial Assets
Cash and due from banks	415,973,000	84,154,000
Federal funds sold	1,308,000	926,000
Certificates of deposit investments	2,695,000	4,625,000
Total available-for-sale securities	879,240,000	685,636,000
Held-to-maturity securities	5,016,000	69,542,000
Equity securities, at fair value	218,000	412,000
Loans held for sale	1,924,000	1,820,000
Loans net of allowance for credit losses	3,094,585,000	2,666,616,000
Interest receivable	19,287,000	15,577,000
Federal Reserve Bank stock	9,401,000	9,401,000
Federal Home Loan Bank stock	5,450,000	4,105,000
Financial Liabilities
Deposits	3,692,784,000	2,917,336,000
Securities sold under agreements to repurchase	206,937,000	208,109,000
Interest payable	2,345,000	2,261,000
Federal Home Loan Bank borrowings	93,969,000	113,895,000
Other borrowings	0	5,000,000
Carrying Amount \| Subordinated Debt
Financial Liabilities
Subordinated debentures	94,253,000
Carrying Amount \| Junior Subordinated Debentures
Financial Liabilities
Subordinated debentures	19,027,000	18,858,000
Fair Value
Financial Assets
Cash and due from banks	415,973,000	84,154,000
Federal funds sold	1,308,000	926,000
Certificates of deposit investments	2,695,000	4,625,000
Total available-for-sale securities	879,240,000	685,636,000
Held-to-maturity securities	5,119,000	69,572,000
Equity securities, at fair value	218,000	412,000
Loans held for sale	1,924,000	1,820,000
Loans net of allowance for credit losses	3,056,344,000	2,622,053,000
Interest receivable	19,287,000	15,577,000
Federal Reserve Bank stock	9,401,000	9,401,000
Federal Home Loan Bank stock	5,450,000	4,105,000
Financial Liabilities
Deposits	3,697,105,000	2,924,144,000
Securities sold under agreements to repurchase	206,945,000	208,016,000
Interest payable	2,345,000	2,261,000
Federal Home Loan Bank borrowings	96,669,000	114,510,000
Other borrowings	0	5,000,000
Fair Value \| Subordinated Debt
Financial Liabilities
Subordinated debentures	94,253,000
Fair Value \| Junior Subordinated Debentures
Financial Liabilities
Subordinated debentures	$ 14,604,000	$ 15,596,000

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty.

No definition available.