Subsequent Event	12 Months Ended
Dec. 31, 2013
Subsequent Events [Abstract]
Subsequent Events	Subsequent Event In February 2014, the Company issued $690.0 million par value of convertible senior notes. The notes are senior unsecured obligations of the Company, do not bear regular interest and mature in February 2019, unless repurchased or converted prior to maturity. The notes are convertible after August 15, 2018 at any time until the close of business on the second scheduled trading day immediately preceding the maturity date into cash, shares of the Company's common stock or a combination of cash and shares of the Company's common stock at the Company's option. The conversion rate will initially be 11.1651 shares of the Company's common stock per $1,000 which is equivalent to an initial conversion price of approximately $89.56 per share, subject to adjustments in certain events, and represents a potential conversion into 7.7 million shares. To minimize the impact of potential dilution upon conversion of the notes, the Company entered into convertible note hedge transactions with respect to its common stock. The Company paid $101.3 million for the note hedge transactions. The note hedge transactions cover approximately 7.7 million shares of the Company’s common stock at a strike price that corresponds to the initial conversion price of the notes, also subject to adjustment, and are exercisable upon conversion of the notes. The note hedge transactions are intended to reduce the potential dilution upon conversion of the notes in the event that the market value per share of the Company’s common stock, as measured under the notes, at the time of exercise is greater than the conversion price of the notes. Separately, the Company entered into warrant transactions, whereby the Company sold warrants to acquire, subject to anti-dilution adjustments, up to 7.7 million shares of the Company’s common stock at a strike price of approximately $104.49 per share. The Company received aggregate proceeds of $78.0 million from the sale of the warrants. The convertible note hedge and warrant transactions will generally have the effect of increasing the conversion price of the notes to approximately $104.49 per share. The Company used $62.0 million of the proceeds from the offering to repurchase shares of its common stock, concurrent with the issuance of the notes. The repurchase was made in accordance with the stock repurchase plan recently approved by the Board of Directors (Note 10).

Subsequent Event

In February 2014, the Company issued $690.0 million par value of convertible senior notes. The notes are senior unsecured obligations of the Company, do not bear regular interest and mature in February 2019, unless repurchased or converted prior to maturity.

The notes are convertible after August 15, 2018 at any time until the close of business on the second scheduled trading day immediately preceding the maturity date into cash, shares of the Company's common stock or a combination of cash and shares of the Company's common stock at the Company's option. The conversion rate will initially be 11.1651 shares of the Company's common stock per $1,000 which is equivalent to an initial conversion price of approximately $89.56 per share, subject to adjustments in certain events, and represents a potential conversion into 7.7 million shares.

To minimize the impact of potential dilution upon conversion of the notes, the Company entered into convertible note hedge transactions with respect to its common stock. The Company paid $101.3 million for the note hedge transactions. The note hedge transactions cover approximately 7.7 million shares of the Company’s common stock at a strike price that corresponds to the initial conversion price of the notes, also subject to adjustment, and are exercisable upon conversion of the notes. The note hedge transactions are intended to reduce the potential dilution upon conversion of the notes in the event that the market value per share of the Company’s common stock, as measured under the notes, at the time of exercise is greater than the conversion price of the notes.

Separately, the Company entered into warrant transactions, whereby the Company sold warrants to acquire, subject to anti-dilution adjustments, up to 7.7 million shares of the Company’s common stock at a strike price of approximately $104.49 per share. The Company received aggregate proceeds of $78.0 million from the sale of the warrants. The convertible note hedge and warrant transactions will generally have the effect of increasing the conversion price of the notes to approximately $104.49 per share.

The Company used $62.0 million of the proceeds from the offering to repurchase shares of its common stock, concurrent with the issuance of the notes. The repurchase was made in accordance with the stock repurchase plan recently approved by the Board of Directors (Note 10).