Fair Value: Schedule of quantitative information about Level 3 Fair Value Measurements on a nonrecurring basis (Details) - Significant Unobservable Inputs (Level 3) - Market Approach Valuation Technique - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Loans Receivable
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unobservable Input(s)	Expected values of future cash flows	Expected values of future cash flows
Loans Receivable | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of financial instruments, range	0.00%	0.00%
Loans Receivable | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of financial instruments, range	0.00%	0.00%
Loans Receivable | Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of financial instruments, range	0.00%	0.00%
Loans Receivable | Fair Value, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 28,102	$ 21,392
Other Real Estate Owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unobservable Input(s)	Estimated selling price less selling costs	Estimated selling price less selling costs
Other Real Estate Owned | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of financial instruments, range	0.00%	0.00%
Other Real Estate Owned | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of financial instruments, range	0.00%	0.00%
Other Real Estate Owned | Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of financial instruments, range	0.00%	0.00%
Other Real Estate Owned | Fair Value, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 0	$ 454