Treasury Stock	6 Months Ended
Jun. 30, 2017
Equity [Abstract]
TREASURY STOCK	TREASURY STOCK Stock Repurchase Program The Company’s Board of Directors authorized an ongoing stock repurchase program with a total repurchase authority granted to the Company of $6.8 billion, of which $500.0 million was approved in January 2017. 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 June 30, 2017, $404.0 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 offering, as well as proceeds from employee stock option 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. During the three months ended June 30, 2017, the Company had no open market purchases. During the six months ended June 30, 2017, the Company expended $500.0 million on open market purchases under the stock repurchase program, repurchasing 6,399,499 shares of outstanding common stock at an average price of $78.13. During the three months ended June 30, 2016, the Company had no open market purchases. During the six months ended June 30, 2016, the Company expended $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 three months ended June 30, 2017, the Company withheld 43,446 shares from equity awards that vested, totaling $3.6 million, to satisfy minimum tax withholding obligations that arose on the vesting of such equity awards. During the six months ended June 30, 2017, the Company withheld 734,600 shares from stock units that vested, totaling $60.5 million, to satisfy minimum tax withholding obligations that arose on the vesting of stock units. During the three months ended June 30, 2016, the Company withheld 134,771 shares from equity awards that vested, totaling $11.0 million, to satisfy minimum tax withholding obligations that arose on the vesting of such equity awards. During the six months ended June 30, 2016, the Company withheld 563,609 shares from stock units that vested, totaling $43.9 million, to satisfy minimum tax withholding obligations that arose on the vesting of stock units. These shares are reflected as treasury stock in the Company’s condensed consolidated balance sheets and the related cash outlays do not reduce the Company’s total stock repurchase authority.

TREASURY STOCK

Stock Repurchase Program

The Company’s Board of Directors authorized an ongoing stock repurchase program with a total repurchase authority granted to the Company of $6.8 billion, of which $500.0 million was approved in January 2017. 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 June 30, 2017, $404.0 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 offering, as well as proceeds from employee stock option 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.

During the three months ended June 30, 2017, the Company had no open market purchases. During the six months ended June 30, 2017, the Company expended $500.0 million on open market purchases under the stock repurchase program, repurchasing 6,399,499 shares of outstanding common stock at an average price of $78.13.

During the three months ended June 30, 2016, the Company had no open market purchases. During the six months ended June 30, 2016, the Company expended $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 three months ended June 30, 2017, the Company withheld 43,446 shares from equity awards that vested, totaling $3.6 million, to satisfy minimum tax withholding obligations that arose on the vesting of such equity awards. During the six months ended June 30, 2017, the Company withheld 734,600 shares from stock units that vested, totaling $60.5 million, to satisfy minimum tax withholding obligations that arose on the vesting of stock units. During the three months ended June 30, 2016, the Company withheld 134,771 shares from equity awards that vested, totaling $11.0 million, to satisfy minimum tax withholding obligations that arose on the vesting of such equity awards. During the six months ended June 30, 2016, the Company withheld 563,609 shares from stock units that vested, totaling $43.9 million, to satisfy minimum tax withholding obligations that arose on the vesting of stock units. These shares are reflected as treasury stock in the Company’s condensed consolidated balance sheets and the related cash outlays do not reduce the Company’s total stock repurchase authority.