Basis of Presentation and Significant Accounting Policies - Summary of Characterization of Dividend Distributions for Federal Income Tax Purposes (Details) - $ / shares	1 Months Ended		12 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Line Items]
Cash dividend	$ 0.10	$ 0.10	$ 0.400	$ 0.400	$ 0.395
Ordinary income			52.50%	80.70%	72.40%
Long-term capital gain			47.50%	15.50%	18.70%
Return of capital			0.00%	3.80%	8.90%
Total			100.00%	100.00%	100.00%
Ordinary Income [Member]
Income Taxes [Line Items]
Cash dividend			$ 0.210	$ 0.323	$ 0.286
Long-Term Capital Gain [Member]
Income Taxes [Line Items]
Cash dividend			0.190	0.062	0.074
Return of Capital [Member]
Income Taxes [Line Items]
Cash dividend			$ 0.000	$ 0.015	$ 0.035