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Stockholders' Equity (Details) $ / shares in Millions, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2015 USD ($) plan $ / shares shares | Dec. 31, 2014 USD ($) $ / shares shares | Dec. 31, 2013 USD ($) $ / shares shares
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract] |  |  |
Preferred stock, issued | 0 | 0 |
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract] |  |  |
Number of share-based compensation plans | plan | 2 |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Granted (shares) | 669,000 | 675,000 | 576,000
Common stock shares available for future awards | 3,400,000 |  |
Shares vested | 23,000 | 18,000 | 333,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] |  |  |
Nonvested beginning of the year (shares) | 1,376,000 | 927,000 | 727,000
Granted (shares) | 669,000 | 675,000 | 576,000
Vested (shares) | (23,000) | (18,000) | (333,000)
Forfeited (shares) | (370,000) | (208,000) | (43,000)
Nonvested end of the year (shares) | 1,652,000 | 1,376,000 | 927,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward] |  |  |
Beginning balance (in dollars per share) | $ / shares | $ 47.8 | $ 36.9 | $ 38.6
Granted (in dollars per share) | $ / shares | 20.8 | 20.3 | 16.4
Vested (in dollars per share) | $ / shares | (0.8) | (1.0) | (16.4)
Forfeited (in dollars per share) | $ / shares | (10.8) | (8.4) | (1.7)
Ending balance (in dollars per share) | $ / shares | $ 57.0 | $ 47.8 | $ 36.9
Retained Earnings Note Disclosure [Abstract] |  |  |
Undistributed earnings of investees accounted for under equity method | $ | $ 12.0 |  |
Restricted Stock [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Income target attainment measurement period | 3 years |  |
Share based compensation expense | $ | $ 5.5 | $ 2.4 | $ 11.3
Unrecognized compensation expense | $ | 17.9 |  |
Performance Awards [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Unrecognized compensation expense | $ | $ 12.0 |  |
TSR/TSRP Minimum Shares | 0 |  |
TSR/TSRP Target Shares | 869,000 |  |
TSR/TSRP Maximum Shares | 1,738,000 |  |
PRSP 2015 [Member] | Restricted Stock [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Granted (shares) | 461,215 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] |  |  |
Granted (shares) | 461,215 |  |
Long-Term Shareholder Value (LTSV) 2015 [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Performance Metric, Percent Expected to be Attained | 85.00% |  |
Long-Term Shareholder Value (LTSV) 2015 [Member] | Restricted Stock [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Granted (shares) | 126,421 |  |
Award vesting period | 3 years |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] |  |  |
Granted (shares) | 126,421 |  |
Long-Term Shareholder Value (LTSV) 2014 [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Performance Metric, Percent Expected to be Attained | 100.00% |  |
PRSP 2012 [Member] | Restricted Stock [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] |  |  |
Forfeited (shares) |  | (171,083) |
PRSP 2013 [Member] | Restricted Stock [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] |  |  |
Forfeited (shares) | (244,899) |  |
TSRP 2013-2015 [Member] | Performance Awards [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
TSR/TSRP Award Fair Value | $ | $ 10.5 |  |
Unrecognized compensation expense | $ | $ 0.0 |  |
TSR/TSRP Minimum Shares | 0 |  |
TSR/TSRP Target Shares | 296,000 |  |
TSR/TSRP Maximum Shares | 592,000 |  |
TSR 2014-2016 [Member] | Performance Awards [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Target share award level | 328,564 |  |
TSR/TSRP Award Fair Value | $ | $ 13.4 |  |
Unrecognized compensation expense | $ | $ 8.9 |  |
TSR/TSRP Minimum Shares | 0 |  |
TSR/TSRP Target Shares | 296,000 |  |
TSR/TSRP Maximum Shares | 592,000 |  |
TSR and TSRP Awards [Member] | Performance Awards [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Share based compensation expense | $ | $ 10.6 | $ 9.8 | $ 12.3
Performance measurement period | 3 years |  |
Common stock shares available for future awards | 2,050,000 |  |
TSR 2014-2016 [Member] | Performance Awards [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
TSR/TSRP Award Fair Value | $ | $ 9.3 |  |
Unrecognized compensation expense | $ | $ 3.1 |  |
TSR/TSRP Minimum Shares | 0 |  |
TSR/TSRP Target Shares | 277,000 |  |
TSR/TSRP Maximum Shares | 554,000 |  |
Maximum [Member] | Restricted Stock [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Award vesting period | 5 years |  |
Maximum [Member] | TSR and TSRP Awards [Member] | Performance Awards [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Award multiplier | 2 |  |
Minimum [Member] | Restricted Stock [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Award vesting period | 3 years |  |
Minimum [Member] | TSR and TSRP Awards [Member] | Performance Awards [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Award multiplier | 0 |  |

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