Stock-Based Compensation Stock Option Summary (Details) - Employee Stock Option [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended				6 Months Ended
		Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2015	Jun. 30, 2014
[Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term		5 years 5 months 15 days		1 day		5 years 5 months 15 days	5 years 5 months 15 days
Outstanding, beginning balance, Number						1,123	1,180
Outstanding, beginning balance, Weighted Average Exercise Price Per Share						$ 51.90	$ 54.79
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term			4 years 5 months		4 years 7 months 22 days	5 years 7 months 30 days	4 years 7 months 30 days
Outstanding, beginning balance, Aggregate Intrinsic Value	[1]					$ 1,676	$ 1,300
Options granted, number						207	147
Granted, Weighted Average Exercise Price Per Share						$ 35.30	$ 35.19
Granted, Weighted Average Grant Date Fair Value						$ 12.15	$ 13.64
Exercised, Number						(23)	(33)
Exercised, Weighted Average Exercise Price Per Share						$ 36.05	$ 23.70
Exercised, Aggregate Intrinsic Value	[1]					$ 26	$ 510
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares						17
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Weighted Average Grant Date Fair Value						$ 37.47
Expired, Number						(158)	(10)
Expired, Weighted Average Exercise Price Per Share						$ 54.25	$ 43.82
Outstanding, ending balance, Number		1,132	1,123	1,284	1,180	1,132	1,284
Outstanding, ending balance, Weighted Average Exercise Price Per Share		$ 49.12	$ 51.90	$ 53.43	$ 54.79	$ 49.12	$ 53.43
Outstanding, ending balance, Aggregate Intrinsic Value	[1]	$ 0	$ 1,676	$ 1,364	$ 1,300	$ 0	$ 1,364
Exercisable, Number		743				743
Exercisable, Weighted Average Exercise Price Per Share		$ 55.53				$ 55.53
Exercisable, Weighted Average Remaining Contractual Term						3 years 11 months 1 day
Exercisable, Aggregate Intrinsic Value	[1]	$ 0				$ 0
Expected to Vest [Member]
[Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term						9 years
Outstanding, ending balance, Number		376				376
Outstanding, ending balance, Weighted Average Exercise Price Per Share		$ 36.90				$ 36.90
Outstanding, ending balance, Aggregate Intrinsic Value	[1]	$ 0				$ 0

[1] The aggregate intrinsic value of outstanding stock options represents amounts that would have been received by the optionees had all in- the-money options been exercised on that date. Specifically, it is the amount by which the market value of our stock exceeded the exercise price of the outstanding in-the-money options before applicable income taxes, based on our closing stock price on the last business day of the period. The aggregate intrinsic value of stock options exercised during the period is calculated based on our stock price at the date of exercise.