Real Estate and Lease Intangibles - Real Estate Starwood Disposition (Details) - Property	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Real Estate [Line Items]
Properties disposed	5	99
Disposed Units	1,194	29,776
Starwood Portfolio [Member]
Real Estate [Line Items]
Properties disposed		72
Disposed Units		23,262
South Florida | Starwood Portfolio [Member]
Real Estate [Line Items]
Properties disposed		33
Disposed Units		10,742
Denver | Starwood Portfolio [Member]
Real Estate [Line Items]
Properties disposed		18
Disposed Units		6,635
Washington D.C. | Starwood Portfolio [Member]
Real Estate [Line Items]
Properties disposed		10
Disposed Units		3,020
Seattle | Starwood Portfolio [Member]
Real Estate [Line Items]
Properties disposed		8
Disposed Units		1,721
Los Angeles | Starwood Portfolio [Member]
Real Estate [Line Items]
Properties disposed		3
Disposed Units		1,144