Capital Stock (Tables)

12 Months Ended

Dec. 31, 2015

Equity [Abstract]

Stock Repurchases Pursuant To Board Of Director Authorizations

The remaining repurchases were made pursuant to the following authorizations (in millions of shares):

	Shares Repurchased			Authorization Remaining at December 31, 2015
Board of Directors’ Authorization	2015	2014	2013
1997 Authorization	0.9	3.2	—	—
2007 Authorization	0.9	5.8	7.7	—
2014 Authorization	20.0	—	—	—
2015 Authorization	6.0	—	—	9.0
Total	27.8	9.0	7.7	9.0