Loans Receivable, Net - Additional Information (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables 90 days past due and still accruing	$ 0	$ 0
Troubled debt restructured loans	16,600,000	17,500,000
Non-accrual loan total troubled debt restructurings	5,100,000	5,500,000
Specific reserves to loans accruing troubled debt restructurings	0	0
Troubled debt restructured loans with accrual interest	11,500,000	12,000,000.0
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in mortgage and consumer loans collateralized, foreclosure amount	1,600,000	1,900,000
Commercial real estate – owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in mortgage and consumer loans collateralized, foreclosure amount	12,300,000	13,800,000
Commercial Real Estate – Investor
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in mortgage and consumer loans collateralized, foreclosure amount	18,500,000	18,300,000
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in mortgage and consumer loans collateralized, foreclosure amount	1,300,000	1,400,000
Foreclosed property held	$ 106,000	$ 106,000