Stockholders' Equity Matters - Additional Information (Details) $ in Thousands		1 Months Ended	12 Months Ended
	Dec. 12, 2017 bank shares	Jan. 31, 2018 USD ($) shares	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Percent of dividends paid			100.00%	100.00%	100.00%
Equity Offering
Class of Stock [Line Items]
Number of banks | bank	16
Sale of stock, number of shares issued in transaction (in shares)	14,500,000
Over-Allotment Option
Class of Stock [Line Items]
Sale of stock, number of shares issued in transaction (in shares)		2,175,000
Sale of stock, consideration received on transaction | $		$ 76,200
Capital gains
Class of Stock [Line Items]
Percent of dividends paid			49.50%	14.70%	5.80%