Dividends Declared and Paid - Additional 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]
Common shares, dividend declared per share	$ 0.07	$ 0.07	$ 0.07	$ 0.07	$ 0.07	$ 0.07	$ 0.21	$ 0.21	$ 0.42	$ 0.375
Long-term incentive plan (LTIP) units, distributions per unit	$ 0.07	$ 0.07	$ 0.07	$ 0.07	$ 0.07	$ 0.07	$ 0.21	$ 0.21	$ 0.42	$ 0.375