Stock-based Compensation (Details)		3 Months Ended		9 Months Ended
	Feb. 20, 2014 $ / shares	Sep. 30, 2015 USD ($) $ / shares	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) director $ / shares shares	Sep. 30, 2014 USD ($)
Stock-based Compensation arrangements
Stock based compensation expense | $		$ (2,900,000)	$ 5,700,000	$ 11,600,000	$ 15,100,000
Tax benefits realized for stock-based compensation | $				0	6,000,000
Supplemental Employee Incentive Plan IV
Stock-based Compensation arrangements
Stock based compensation expense | $		$ (100,000)	$ 200,000	$ (200,000)	$ 3,300,000
Interim price goal (in dollars per share)		$ 55.00		$ 55.00
Assumptions:
Stock price volatility				39.30%
Risk free rate of return				0.60%
Annual salary increase rate				4.00%
Annual turnover rate				4.60%
Restricted Stock Awards
Stock-based Compensation arrangements
Granted (in shares) | shares				3,400
Granted (in dollars per share)				$ 28.55
Annual forfeiture rate assumption (as a percent)				5.00%
Restricted Stock Units
Stock-based Compensation arrangements
Granted (in shares) | shares				49,447
Granted (in dollars per share)				$ 28.02
Common stock issued (in shares) | shares				230,068
Common stock issued, weighted average grant date per unit value (in dollars per share)				$ 13.45
Common stock issued, number of recipients | director				2
Performance Share Awards | Minimum
Stock-based Compensation arrangements
Annual forfeiture rate assumption (as a percent)				0.00%
Performance Share Awards | Maximum
Stock-based Compensation arrangements
Annual forfeiture rate assumption (as a percent)				5.00%
Performance Share Awards Based on Internal Performance Metrics
Stock-based Compensation arrangements
Right to receive additional shares, maximum (as a percent)				100.00%
Employee Performance Share Awards
Stock-based Compensation arrangements
Granted (in shares) | shares				349,780
Granted (in dollars per share)				$ 27.71
Number of years over which performance criteria is to be met				3 years
Hybrid Performance Share Awards
Stock-based Compensation arrangements
Granted (in shares) | shares				194,947
Granted (in dollars per share)				$ 27.71
Vesting rights				The 2015 awards vest 25% on each of the first and second anniversary dates and 50% on the third anniversary
Minimum operating cash flow for the year preceding the performance period | $				$ 100,000,000
Hybrid Performance Share Awards | Hybrid performance share awards, percentage vesting on each of the first and second anniversary
Stock-based Compensation arrangements
Award vesting rights, percentage		25.00%
Hybrid Performance Share Awards | Hybrid performance share awards, percentage vesting on the third anniversary
Stock-based Compensation arrangements
Award vesting rights, percentage		50.00%
Performance Shares Based on Market Conditions
Stock-based Compensation arrangements
Right to receive shares (as a percent)				100.00%
Right to receive an additional award in cash (as a percent)				100.00%
TSR Performance Share Awards
Stock-based Compensation arrangements
Granted (in shares) | shares				292,421
Granted (in dollars per share)	$ 19.29
Performance period				3 years
Assumptions:
Fair value per performance share award, minimum (in dollars per share)				$ 7.66
Fair value per performance share award, maximum(in dollars per share)				$ 10.04
Stock price volatility	32.30%
Stock price volatility, minimum				29.80%
Stock price volatility, maximum				39.20%
Risk free rate of return	1.00%
Risk free rate of return, minimum				0.00%
Risk free rate of return, maximum				0.70%
Expected dividend yield	0.30%			0.40%