Capital Stock (Details 3) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restricted stock units
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	810	0	301
Stock options
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	89	98	188
Stock Appreciation Rights (SARs)
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	1,458	1,142	912
Performance Shares [Member]
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	684	278	0