Securities - Other securities policy (Details)	Mar. 31, 2021 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Number of Pooled Trust Preferred Securities	2
Fair Value of Pooled Trust Preferred Securities Held	$ 735,000
Unrealized Losses on Pooled Trust Preferred Securities in a Continuous Unrealized Loss Position for 12 Months or More	$ 241,000
Prepayments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, Input rate	1.8
Annual defaults
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, Input rate	2.20
Basis points thereafter	0.68
Recovery rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, Input rate	7
Lagged years
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, Input term	2 years