Dividends Declared and Paid - Dividend Information (Details) (USD $)	1 Months Ended						3 Months Ended		6 Months Ended
	Jun. 30, 2013	May 31, 2013	Apr. 30, 2013	Mar. 31, 2013	Feb. 28, 2013	Jan. 31, 2013	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2013	Jun. 30, 2012
Equity [Abstract]
Record Date	Jun. 28, 2013	May 31, 2013	Apr. 30, 2013	Mar. 29, 2013	Feb. 28, 2013	Jan. 31, 2013
Payment Date	Jul. 26, 2013	Jun. 28, 2013	May 31, 2013	Apr. 26, 2013	Mar. 29, 2013	Feb. 22, 2013
Common share distribution amount	$ 0.07	$ 0.07	$ 0.07	$ 0.07	$ 0.07	$ 0.07	$ 0.21	$ 0.21	$ 0.42	$ 0.375
LTIP unit distribution amount	$ 0.07	$ 0.07	$ 0.07	$ 0.07	$ 0.07	$ 0.07	$ 0.21	$ 0.21	$ 0.42	$ 0.375