Capital Stock	12 Months Ended
Dec. 31, 2018
Equity [Abstract]
CAPITAL STOCK	CAPITAL STOCK Stock Repurchase Programs The Company’s Board of Directors authorized an ongoing stock repurchase program, of which $1.7 billion was approved in November 2017 and $750.0 million was approved in October 2018. The Company may use the approved dollar authority to repurchase stock at any time until the approved amount is exhausted. The objective of the Company’s stock repurchase program is to improve stockholders’ returns. At December 31, 2018, approximately $767.9 million was available to repurchase common stock pursuant to the stock repurchase program. All shares repurchased are recorded as treasury stock. A portion of the funds used to repurchase stock over the course of the program was provided by net proceeds from the Convertible Notes and 2027 Notes offerings, as well as proceeds from employee stock awards exercises and the related tax benefit. The Company is authorized to make open market purchases of its common stock using general corporate funds through open market purchases, pursuant to a Rule 10b5-1 plan or in privately negotiated transactions. In November 2017, the Company purchased $750.0 million of shares of its common stock through the ASR agreement with the ASR counterparty. The Company paid $750.0 million to the ASR counterparty under the ASR agreement and received approximately 7.1 million shares of its common stock from the ASR counterparty, which represented 80 percent of the value of the shares to be repurchased pursuant to the ASR agreement. The total number of shares of common stock that the Company repurchased under the ASR agreement was based on the average of the daily volume-weighted average prices of its common stock during the term of the ASR agreement, less a discount. Final settlement of the ASR agreement was completed in January 2018 and the Company received delivery of an additional 1.4 million shares of its common stock. In February 2018, the Company entered into an ASR transaction with a counterparty to pay an aggregate of $750.0 million in exchange for the immediate delivery of approximately 6.5 million shares of its common stock based on current market prices. The purchase price per share under the ASR was based on the volume-weighted average price of the Company's common stock during the term of the ASR, less a discount. The ASR was entered into pursuant to the Company's existing share repurchase program. Final settlement of the ASR agreement was completed in April 2018 and the Company received delivery of an additional 1.6 million additional shares of its common stock. During the year ended December 31, 2018, the Company expended approximately $511.2 million on open market purchases under the stock repurchase program, repurchasing 4,730,542 shares of outstanding common stock at an average price of $108.05 During the year ended December 31, 2017, the Company expended approximately $575.0 million on open market purchases under the stock repurchase program, repurchasing 7,384,368 shares of outstanding common stock at an average price of $77.86. During the year ended December 31, 2016, the Company expended approximately $28.7 million on open market purchases under the stock repurchase program, repurchasing 426,300 shares of outstanding common stock at an average price of $67.30. Shares for Tax Withholding During the years ended December 31, 2018, 2017 and 2016, the Company withheld 739,522 shares, 974,501 shares and 830,155 shares, respectively, from equity awards that vested. Amounts withheld to satisfy minimum tax withholding obligations that arose on the vesting of equity awards was $71.6 million, $80.0 million and $66.6 million, for 2018, 2017 and 2016, respectively. These shares are reflected as treasury stock in the Company's consolidated balance sheets and the related cash outlays do not reduce the Company's total stock repurchase authority. Preferred Stock The Company is authorized to issue 5,000,000 shares of preferred stock, $0.01 par value per share. No shares of such preferred stock were issued and outstanding at December 31, 2018 or 2017. Cash Dividend On October 24, 2018, the Company announced that its Board of Directors approved a quarterly cash dividend of $0.35 per share which was paid on December 21, 2018 to all shareholders of record as of the close of business on December 7, 2018. Subsequent Event On January 23, 2019, the Company announced that its Board of Directors approved a quarterly cash dividend of $0.35 per share. This dividend is payable on March 22, 2019 to all shareholders of record as of the close of business on March 8, 2019. Future dividends will be subject to Board approval.

CAPITAL STOCK

Stock Repurchase Programs

The Company’s Board of Directors authorized an ongoing stock repurchase program, of which $1.7 billion was approved in November 2017 and $750.0 million was approved in October 2018. The Company may use the approved dollar authority to repurchase stock at any time until the approved amount is exhausted. The objective of the Company’s stock repurchase program is to improve stockholders’ returns. At December 31, 2018, approximately $767.9 million was available to repurchase common stock pursuant to the stock repurchase program. All shares repurchased are recorded as treasury stock. A portion of the funds used to repurchase stock over the course of the program was provided by net proceeds from the Convertible Notes and 2027 Notes offerings, as well as proceeds from employee stock awards exercises and the related tax benefit. The Company is authorized to make open market purchases of its common stock using general corporate funds through open market purchases, pursuant to a Rule 10b5-1 plan or in privately negotiated transactions.

In November 2017, the Company purchased $750.0 million of shares of its common stock through the ASR agreement with the ASR counterparty. The Company paid $750.0 million to the ASR counterparty under the ASR agreement and received approximately 7.1 million shares of its common stock from the ASR counterparty, which represented 80 percent of the value of the shares to be repurchased pursuant to the ASR agreement. The total number of shares of common stock that the Company repurchased under the ASR agreement was based on the average of the daily volume-weighted average prices of its common stock during the term of the ASR agreement, less a discount. Final settlement of the ASR agreement was completed in January 2018 and the Company received delivery of an additional 1.4 million shares of its common stock.

In February 2018, the Company entered into an ASR transaction with a counterparty to pay an aggregate of $750.0 million in exchange for the immediate delivery of approximately 6.5 million shares of its common stock based on current market prices. The purchase price per share under the ASR was based on the volume-weighted average price of the Company's common stock during the term of the ASR, less a discount. The ASR was entered into pursuant to the Company's existing share repurchase program. Final settlement of the ASR agreement was completed in April 2018 and the Company received delivery of an additional 1.6 million additional shares of its common stock.

During the year ended December 31, 2018, the Company expended approximately $511.2 million on open market purchases under the stock repurchase program, repurchasing 4,730,542 shares of outstanding common stock at an average price of $108.05

During the year ended December 31, 2017, the Company expended approximately $575.0 million on open market purchases under the stock repurchase program, repurchasing 7,384,368 shares of outstanding common stock at an average price of $77.86.

During the year ended December 31, 2016, the Company expended approximately $28.7 million on open market purchases under the stock repurchase program, repurchasing 426,300 shares of outstanding common stock at an average price of $67.30.

Shares for Tax Withholding

During the years ended December 31, 2018, 2017 and 2016, the Company withheld 739,522 shares, 974,501 shares and 830,155 shares, respectively, from equity awards that vested. Amounts withheld to satisfy minimum tax withholding obligations that arose on the vesting of equity awards was $71.6 million, $80.0 million and $66.6 million, for 2018, 2017 and 2016, respectively. These shares are reflected as treasury stock in the Company's consolidated balance sheets and the related cash outlays do not reduce the Company's total stock repurchase authority.

Preferred Stock

The Company is authorized to issue 5,000,000 shares of preferred stock, $0.01 par value per share. No shares of such preferred stock were issued and outstanding at December 31, 2018 or 2017.

Cash Dividend

On October 24, 2018, the Company announced that its Board of Directors approved a quarterly cash dividend of $0.35 per share which was paid on December 21, 2018 to all shareholders of record as of the close of business on December 7, 2018.

Subsequent Event

On January 23, 2019, the Company announced that its Board of Directors approved a quarterly cash dividend of $0.35 per share. This dividend is payable on March 22, 2019 to all shareholders of record as of the close of business on March 8, 2019. Future dividends will be subject to Board approval.