Employee Benefit Plan (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 1988	Dec. 31, 1987	Dec. 31, 2018	Dec. 31, 1985
Defined Benefit Plan Disclosure [Line Items]
Amount borrowed						$ 2,000,000
Employee stock ownership plan debt structure interest rate description	prime rate
Employee stock ownership plan, term of loan	40 years
Employee stock ownership plan, amount of additional loan			$ 1,942,000	$ 1,942,000
Outstanding shares subject to repurchase obligation	0
ESOP, number of allocated shares since inception	398,283
ESOP, number of unallocated shares	71,744	87,426
ESOP, compensation expenses	$ 101,000	$ 101,000
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Future obligation of benefits	2,529,000	$ 2,126,000			$ 1,730,000
Net loss to be amortized from AOCI to benefit cost	$ 77,000
Medical inflation rate for next year	10.00%
Grading down percentage for each year	0.50%
Floor rate	5.00%