Other Assets - Additional Information (Detail) $ in Millions		9 Months Ended	12 Months Ended
	May 30, 2018 USD ($)	Sep. 30, 2018 Hotel Room	Dec. 31, 2017 Hotel Room
Other Assets [Line Items]
Number of hotels classified as assets held for sale | Hotel		1	3
Number of hotel rooms held for sale | Room		150	400
CMBS Loan Agreement [Member]
Other Assets [Line Items]
Aggregate notional amount | $	$ 1,035
LIBOR floor percentage	3.25%
Interest rate swap agreement expiration date	Jul. 15, 2020