Loans - Narrative (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2022 USD ($) forbearanceAgreement Contract application	Mar. 31, 2021 USD ($) Security	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period for order of valuations (at least)	18 months
Troubled debt restructured loans, balance	$ 3,592,000	$ 3,764,000
Number of loans which has periodic late payments | Contract	1
Number of contracts with active forbearance agreements | forbearanceAgreement	0
Consumer mortgage loans secured by residential real estate properties for which formal foreclosure proceedings are in process	$ 767,000		$ 399,000
Recognized loan fee income	$ 16,090,000	17,798,000
Residential mortgage and commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Threshold period past due to discontinue accrual interest on financing receivable	90 days
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Threshold period past due for write-off of financing receivable (no later than)	120 days
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period of financing receivable, updated valuation on real estate secured loans (number of days past due)	90 days
Number of previous months with no updated valuation completed for corporation to update valuation	12 months
Impaired financing receivable, valuation on real estate collateralized loans (number of days after the loan is classified as impaired)	30 days
CARES Act
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructured loans, balance		$ 23,720,360
Number of applications | application	2,217
Total amount under PPP (up to)	$ 223,036,703
Projected fee income	9,500,000
Recognized loan fee income	468,000		$ 5,627,000	$ 2,875,000
Number of Loans | Security		30
Percent of loan portfolio		0.016
PPP loans	$ 9,844,452
Maximum | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable term	20 years
Loan-to-value ratio (no greater than)	80.00%
Maximum | Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable term	30 years
Loan-to-value ratio (no greater than)	80.00%
Loan-to-value ratio that requires private mortgage insurance (in excess of)	80.00%
Maximum | Home equity lines of credit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable term	20 years
Loan-to-value ratio (no greater than)	90.00%
Nonaccrual
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructured loans, balance	$ 47,000	$ 111,000
Accrual
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructured loans, balance	$ 3,545,000	$ 3,653,000