SUBSEQUENT EVENT	3 Months Ended
Mar. 31, 2017
Subsequent Events [Abstract]
SUBSEQUENT EVENT	12. SUBSEQUENT EVENT In May 2017, the Company issued $517.5 million aggregate principal amount of 2.25% Convertible Senior Notes due May 2024. Debt issuance costs of approximately $15.3 million were primarily comprised of initial purchasers’ discounts and commissions, legal, accounting, and other professional fees, a portion of which will be capitalized and are recorded as a reduction to long-term debt and are being amortized using the effective interest method to interest expense over the seven-year term of the notes. The remaining debt issuance costs will be allocated as a component of equity in additional paid-in capital. The notes will be convertible into cash, shares of common stock, or a combination of cash and shares of common stock based on an initial conversion rate, subject to adjustment, of 13.1711 shares per $1,000 principal amount of the notes (which represents an initial conversion price of approximately $75.92 per share). The notes will mature on May 15, 2024, unless earlier converted, redeemed or repurchased. Prior to the close of business on the business day immediately preceding January 15, 2024, the notes will be convertible at the option of the holders only upon satisfaction of certain circumstances. Thereafter, the notes will be convertible at the option of the holders at any time up until the close of business on the scheduled trading day immediately preceding May 15, 2024. The Company may not redeem the notes prior to May 15, 2021. On or after this date, the Company, at its election, may redeem all, or any portion, of the notes for cash if the last reported sales price of the Company’s common stock, for at least 20 trading days (whether or not consecutive) during the period of 30 consecutive trading days ending on the last trading day immediately preceding the date which the Company sends the related redemption notice, is more than 130% of the conversion price of the notes in effect on each applicable trading day. It is the Company’s intent and policy to settle conversions through combination settlement, which essentially involves repayment of an amount of cash equal to the “principal portion” and delivery of the “share amount” in excess of the principal portion in shares of common stock or cash. In general, for each $1,000 in principal, the “principal portion” of cash upon settlement is defined as the lesser of $1,000, and the conversion value during the 25-day observation period as described in the indenture for the notes. The conversion value is the sum of the daily conversion value which is the product of the effective conversion rate divided by 25 days and the daily volume weighted average price (VWAP) of the Company’s common stock. The “share amount” is the cumulative “daily share amount” during the observation period, which is calculated by dividing the daily VWAP into the difference between the daily conversion value (i.e., conversion rate x daily VWAP) and $1,000. The Company pays 2.25% interest per annum on the principal amount of the notes semi-annually in arrears in cash on May 15 and November 15 of each year. The Company will account separately for the liability and equity components of the notes in accordance with authoritative guidance for convertible debt instruments that may be settled in cash upon conversion. If a fundamental change, as defined in the indenture for the notes, such as an acquisition, merger, or liquidation of the Company, occurs prior to the maturity date, subject to certain limitations, holders of the notes may require the Company to repurchase all or a portion of their notes for cash at a repurchase price equal to 100% of the principal amount of the notes to be repurchased, plus any accrued and unpaid interest, and additional fees.

12. SUBSEQUENT EVENT

In May 2017, the Company issued $517.5 million aggregate principal amount of 2.25% Convertible Senior Notes due May 2024. Debt issuance costs of approximately $15.3 million were primarily comprised of initial purchasers’ discounts and commissions, legal, accounting, and other professional fees, a portion of which will be capitalized and are recorded as a reduction to long-term debt and are being amortized using the effective interest method to interest expense over the seven-year term of the notes. The remaining debt issuance costs will be allocated as a component of equity in additional paid-in capital.

The notes will be convertible into cash, shares of common stock, or a combination of cash and shares of common stock based on an initial conversion rate, subject to adjustment, of 13.1711 shares per $1,000 principal amount of the notes (which represents an initial conversion price of approximately $75.92 per share). The notes will mature on May 15, 2024, unless earlier converted, redeemed or repurchased. Prior to the close of business on the business day immediately preceding January 15, 2024, the notes will be convertible at the option of the holders only upon satisfaction of certain circumstances. Thereafter, the notes will be convertible at the option of the holders at any time up until the close of business on the scheduled trading day immediately preceding May 15, 2024. The Company may not redeem the notes prior to May 15, 2021. On or after this date, the Company, at its election, may redeem all, or any portion, of the notes for cash if the last reported sales price of the Company’s common stock, for at least 20 trading days (whether or not consecutive) during the period of 30 consecutive trading days ending on the last trading day immediately preceding the date which the Company sends the related redemption notice, is more than 130% of the conversion price of the notes in effect on each applicable trading day.

It is the Company’s intent and policy to settle conversions through combination settlement, which essentially involves repayment of an amount of cash equal to the “principal portion” and delivery of the “share amount” in excess of the principal portion in shares of common stock or cash. In general, for each $1,000 in principal, the “principal portion” of cash upon settlement is defined as the lesser of $1,000, and the conversion value during the 25-day observation period as described in the indenture for the notes. The conversion value is the sum of the daily conversion value which is the product of the effective conversion rate divided by 25 days and the daily volume weighted average price (VWAP) of the Company’s common stock. The “share amount” is the cumulative “daily share amount” during the observation period, which is calculated by dividing the daily VWAP into the difference between the daily conversion value (i.e., conversion rate x daily VWAP) and $1,000.

The Company pays 2.25% interest per annum on the principal amount of the notes semi-annually in arrears in cash on May 15 and November 15 of each year. The Company will account separately for the liability and equity components of the notes in accordance with authoritative guidance for convertible debt instruments that may be settled in cash upon conversion.

If a fundamental change, as defined in the indenture for the notes, such as an acquisition, merger, or liquidation of the Company, occurs prior to the maturity date, subject to certain limitations, holders of the notes may require the Company to repurchase all or a portion of their notes for cash at a repurchase price equal to 100% of the principal amount of the notes to be repurchased, plus any accrued and unpaid interest, and additional fees.