CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) - $ / shares				3 Months Ended		12 Months Ended
	Mar. 06, 2019	Feb. 15, 2019	Apr. 15, 2013	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Preferred Stock, dividend rate				7.50%		7.50%
Common stock, cash dividends declared (in dollars per share)	$ 0.2			$ 0.20	$ 0.20
Preferred Stock 7.50% Series B Cumulative Redeemable - Liquidation Preference $25.00 per Share
Dividend declared per share, preferred stock (in dollars per share)		$ 0.46875		$ 0.46875	$ 0.46875
Preferred Stock | Preferred Stock 7.50% Series B Cumulative Redeemable - Liquidation Preference $25.00 per Share
Preferred Stock, dividend rate			7.50%	7.50%	7.50%
Preferred Stock, liquidation preference per share (in dollars per share)			$ 25.00	$ 25.00		$ 25