Borrowed Funds - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2018
Statement of Financial Position [Abstract]
FHLB advance prepayment fees	$ 13,333	$ 0	$ 924	$ 0	$ 14,257	$ 0
Minimum investment in the capital stock of the FHLB (percent)					0.125%
Specified value of certain transactions between the Bank and the FHLB (percent)					4.50%