Equity-Based Compensation	6 Months Ended
Jun. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Equity-Based Compensation	Equity-Based Compensation On December 31, 2017, 321,880 Performance Share Units ("PSUs") under the 2013 Long-Term Incentive Plan vested, representing a vesting rate for the 2015-2017 performance period of 192.0% of target. The PSUs had a weighted-average grant-date fair value of $37.84 per unit. In connection with the PSUs that vested, the Company distributed shares of common stock to each participant during the six months ended June 30, 2018 and withheld the number of shares of common stock equal to the respective tax withholding for each participant. The Company was required to pay withholding taxes of $9 million to federal, state and foreign taxing authorities for the vesting of these PSUs. This amount is reported as a financing activity in the Consolidated Statement of Cash Flows and as an increase to Accumulated Deficit in the Consolidated Statement of Shareholders' Equity for the six months ended June 30, 2018. On December 31, 2016, 748,855 PSUs under the 2013 Long-Term Incentive Plan vested, representing a vesting rate for the 2014-2016 performance period of 193.5% of target. The PSUs had a weighted-average grant-date fair value of $24.40 per unit. In connection with the PSUs that vested, the Company distributed shares of common stock to each participant during the six months ended June 30, 2017 and withheld the number of shares of common stock equal to the respective tax withholding for each participant. The Company was required to pay withholding taxes of $18 million to federal, state and foreign taxing authorities for the vesting of these PSUs. This amount is reported as a financing activity in the Consolidated Statement of Cash Flows and as an increase to Accumulated Deficit in the Consolidated Statement of Shareholders' Equity for the six months ended June 30, 2017. On June 26, 2017, an aggregate of 997,450 Restricted Stock Units ("RSUs") under the 2013 Long-Term Incentive Plan vested. The RSUs had a weighted-average grant-date fair value of $17.04 per unit. In connection with the RSUs that vested, the Company distributed shares of common stock to each participant during the six months ended June 30, 2017 and withheld the number of shares of common stock equal to the respective tax withholding for each participant. The Company was required to pay withholding taxes of $24 million to federal, state and foreign taxing authorities for the vesting of these RSUs. This amount is reported as a financing activity in the Consolidated Statement of Cash Flows and as an increase to Accumulated Deficit in the Consolidated Statement of Stockholders' Equity for the six months ended June 30, 2017.

Equity-Based Compensation

On December 31, 2017, 321,880 Performance Share Units ("PSUs") under the 2013 Long-Term Incentive Plan vested, representing a vesting rate for the 2015-2017 performance period of 192.0% of target. The PSUs had a weighted-average grant-date fair value of $37.84 per unit. In connection with the PSUs that vested, the Company distributed shares of common stock to each participant during the six months ended June 30, 2018 and withheld the number of shares of common stock equal to the respective tax withholding for each participant. The Company was required to pay withholding taxes of $9 million to federal, state and foreign taxing authorities for the vesting of these PSUs. This amount is reported as a financing activity in the Consolidated Statement of Cash Flows and as an increase to Accumulated Deficit in the Consolidated Statement of Shareholders' Equity for the six months ended June 30, 2018.

On December 31, 2016, 748,855 PSUs under the 2013 Long-Term Incentive Plan vested, representing a vesting rate for the 2014-2016 performance period of 193.5% of target. The PSUs had a weighted-average grant-date fair value of $24.40 per unit. In connection with the PSUs that vested, the Company distributed shares of common stock to each participant during the six months ended June 30, 2017 and withheld the number of shares of common stock equal to the respective tax withholding for each participant. The Company was required to pay withholding taxes of $18 million to federal, state and foreign taxing authorities for the vesting of these PSUs. This amount is reported as a financing activity in the Consolidated Statement of Cash Flows and as an increase to Accumulated Deficit in the Consolidated Statement of Shareholders' Equity for the six months ended June 30, 2017.

On June 26, 2017, an aggregate of 997,450 Restricted Stock Units ("RSUs") under the 2013 Long-Term Incentive Plan vested. The RSUs had a weighted-average grant-date fair value of $17.04 per unit. In connection with the RSUs that vested, the Company distributed shares of common stock to each participant during the six months ended June 30, 2017 and withheld the number of shares of common stock equal to the respective tax withholding for each participant. The Company was required to pay withholding taxes of $24 million to federal, state and foreign taxing authorities for the vesting of these RSUs. This amount is reported as a financing activity in the Consolidated Statement of Cash Flows and as an increase to Accumulated Deficit in the Consolidated Statement of Stockholders' Equity for the six months ended June 30, 2017.