Tax Treatment of Distributions - Dividends Tax Treatment (Details) - $ / shares		12 Months Ended
	Jan. 13, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share (in dollars per share)	$ 0.313
Capital gains, federal statutory tax rate		20.00%
Common Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share (in dollars per share)		$ 1.880	$ 1.760	$ 3.500
Tax Treatment, Ordinary income [Member] | Common Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share (in dollars per share)		$ 0.939	$ 1.474	$ 1.356
Dividends paid per common share, percentage		49.95%	83.73%	70.87%
Tax Treatment, Qualified dividend [Member] | Common Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share (in dollars per share)		$ 0.004	$ 0.003	$ 0.002
Dividends paid per common share, percentage		0.21%	0.19%	0.11%
Tax Treatment, Return of capital [Member] | Common Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share (in dollars per share)		$ 0.312	$ 0.275	$ 0.344
Dividends paid per common share, percentage		16.62%	15.64%	18.00%
Tax Treatment, Capital gains [Member] | Common Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share (in dollars per share)		$ 0.600	$ 0.008	$ 0
Dividends paid per common share, percentage		31.93%	0.44%	0.00%
Tax Treatment, Unrecaptured section 1250 gains [Member] | Common Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share (in dollars per share)		$ 0.025	$ 0	$ 0.211
Dividends paid per common share, percentage		1.29%	0.00%	11.02%
Tax treatment [Member] | Common Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share (in dollars per share)		$ 1.880	$ 1.760	$ 1.913
Dividends paid per common share, percentage		100.00%	100.00%	100.00%