Acquisitions - Additional Information (Detail) (USD $)	3 Months Ended			12 Months Ended
	Sep. 30, 2012 Property	Jun. 30, 2012 Property	Mar. 31, 2012 Property	Dec. 31, 2011 Property	Apr. 15, 2011 Homewood Suites	Apr. 27, 2011 Staybridge Suites	Apr. 27, 2011 Holiday Inn	May 16, 2012 Hilton Garden Inn	Feb. 28, 2012 Hilton Garden Inn	May 25, 2011 Hilton Garden Inn	Feb. 28, 2012 Hilton Garden Inn Other Business Acquisition	May 16, 2012 Courtyard by Marriott	Jan. 12, 2012 Courtyard by Marriott	Jul. 28, 2011 Courtyard by Marriott	Jun. 21, 2012 Hampton Inn and Suites	Jun. 21, 2012 Hilton Garden Inn And Hampton Inn And Suites	Jul. 02, 2012 Residence Inn in Arlington, TX
Business Acquisition [Line Items]
Number of hotels acquired	1	3	3	5
Purchase price of acquired entity					$ 7,300,000	$ 10,000,000	$ 7,000,000	$ 11,500,000	$ 11,500,000	$ 13,400,000	$ 8,600,000	$ 15,000,000	$ 28,500,000	$ 12,400,000	$ 8,000,000		$ 15,500,000
Business acquisition, purchase price allocation, liabilities assumed	$ 33,414,000			$ 398,000									$ 19,000,000			$ 14,100,000