Common Shares (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified			1 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	May 31, 2012 2012 ATM Program [Member]
Maximum aggregate offering price of common shares			$ 300
Number of common and preferred stock authorized to issue	185,000,000
Common shares, authorized	175,000,000	175,000,000
Preferred shares, authorized	10,000,000
Common Stock, Shares, Outstanding	85,600,000
Preferred Stock, Shares Outstanding	0