Capital Stock (Tables)

12 Months Ended

Dec. 31, 2013

Class of Stock Disclosures [Abstract]

Common Shares Outstanding and Treasury Shares Held Rollforward Table

Common Shares Outstanding	Year Ended December 31,
	2013	2012	2011
At beginning of period	78,112,032	77,423,415	76,291,745
Exercise of common stock options, net	373,106	580,097	858,727
Grants of restricted stock, net	370,409	108,520	272,943
At end of period	78,855,547	78,112,032	77,423,415

Treasury Shares Held	Year Ended December 31,
	2013	2012	2011
At beginning of period	2,334,137	2,249,959	1,533,653
Shares received upon exercise of common stock options	119,477	81,616	592,992
Shares received upon vesting of restricted stock, net	24,470	2,562	123,314
At end of period	2,478,084	2,334,137	2,249,959