Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Loans held for sale at fair value	$ 18,938	$ 19,592
Allowance for loans losses	$ 18,883	$ 15,842
Stockholders' Equity:
Common stock, without par value (in dollars per share)
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	28,742,484	28,706,438
Common stock, shares outstanding	28,742,484	28,706,438
Preferred stock, without par value (in dollars per share)
Preferred stock, shares authorized	5,000,000	5,000,000
8% Preferred Stock
Stockholders' Equity:
Preferred stock, dividend rate (as a percent)	8.00%	8.00%
Preferred stock liquidation preference (in dollars per share)	$ 1,000	$ 1,000
Preferred stock, shares authorized	50,000	50,000
Preferred stock, shares issued	41,625	41,625
Preferred stock, shares outstanding	41,625	41,625
7% Preferred Stock
Stockholders' Equity:
Preferred stock, dividend rate (as a percent)	7.00%	7.00%
Preferred stock liquidation preference (in dollars per share)	$ 25	$ 25
Preferred stock, shares authorized	3,500,000	3,500,000
Preferred stock, shares issued	2,081,800	2,081,800
Preferred stock, shares outstanding	2,081,800	2,081,800
6% Preferred Stock
Stockholders' Equity:
Preferred stock, dividend rate (as a percent)	6.00%	6.00%
Preferred stock liquidation preference (in dollars per share)	$ 1,000	$ 1,000
Preferred stock, shares authorized	125,000	125,000
Preferred stock, shares issued	125,000	125,000
Preferred stock, shares outstanding	125,000	125,000
Depositary shares	5,000,000	5,000,000