Subsequent Events (Details) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended		0 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Oct. 31, 2014	Oct. 01, 2014	May 06, 2014	Oct. 21, 2014
Senior Unsecured Credit Facility
Subsequent events
Maximum borrowing capacity	300.0
Senior Unsecured Credit Facility | $225 Million Revolver
Subsequent events
Maximum borrowing capacity	225.0				225.0
Common stock
Subsequent events
Common stock issued upon redemption of common units (in shares)	198,292	2,466,404
Subsequent Event | Series A preferred shares
Subsequent events
Cash dividends declared, preferred stock (in dollars per share)			$ 0.578125
Subsequent Event | Series B preferred shares
Subsequent events
Cash dividends declared, preferred stock (in dollars per share)			$ 0.4921875
Subsequent Event | Series C preferred shares
Subsequent events
Cash dividends declared, preferred stock (in dollars per share)			$ 0.4453125
Subsequent Event | Common stock
Subsequent events
Common stock issued upon redemption of common units (in shares)				75,733
Cash dividends declared, common stock (in dollars per share)			$ 0.1175
Subsequent Event | Operating partnership | Non-controlling Interests | Common units
Subsequent events
Common units redeemed				75,733
Subsequent Event | Hotel properties | San Antonio, Texas
Subsequent events
Sale of property previously classified as held for sale						$ 7.9
Subsequent Event | Land | San Antonio, Texas
Subsequent events
Number of properties						3
Area of land parcel						5.64