Income Taxes - Schedule of Per Share Distributions to Stockholders (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Common share distribution	$ 1.010000	$ 0.990000	$ 0.950000
Ordinary income	0.701910	0.438792	0.655535
Capital gains	0.275040	0.551208	0.021022
Unrecaptured Sec. 1250 gain	0.041160	0.132280	0.004647
Section 199A Dividends	0.701910	$ 0.438792
Return of capital	$ 0.033050		$ 0.273443