Property and Equipment - Additional Information (Details) - Land, Buildings and Leasehold Improvements - USD ($) $ in Millions	1 Months Ended
	Sep. 30, 2018	Jul. 31, 2018	Jun. 30, 2018	Feb. 28, 2018
Property Plant And Equipment [Line Items]
Purchase of operating property for future conversion		$ 50		$ 41
New York
Property Plant And Equipment [Line Items]
Purchase of operating property for future conversion			$ 176
Hawaii
Property Plant And Equipment [Line Items]
Purchase of operating property for future conversion	$ 123