Convertible Senior Notes and Capped Call Transactions

6 Months Ended

Jun. 30, 2020

Debt Disclosure [Abstract]

Convertible Senior Notes and Capped Call Transactions

CONVERTIBLE SENIOR NOTES AND CAPPED CALL TRANSACTIONSOn May 11, 2020, the Company issued $253,000 aggregate principal amount of 1.25% Convertible Senior Notes due August 2025 (the “2025 Notes”) pursuant to an Indenture dated May 11, 2020 (the “Indenture”), between the Company and U.S. Bank National Association, as trustee. The offering consisted of $220,000 aggregate principal amount plus the full exercise of the initial purchasers’ option to purchase up to an additional $33,000 aggregate principal amount. The net proceeds to the Company after the initial purchaser discount and issuance costs were approximately $245,158. The Company used $29,348 of the net proceeds from the offering to pay the cost of the capped call transactions described below. The Company expects to use the

remaining net proceeds for working capital and general corporate purposes, which may include research and development, capital expenditures and other general corporate purposes.

The 2025 Notes will mature on August 15, 2025, unless earlier converted, redeemed or repurchased. Interest will be payable semi-annually in arrears on February 15 and August 15 of each year, beginning on August 15, 2020, at a rate of 1.25% per year.

The initial conversion rate for the 2025 Notes is 10.8556 shares of the Company’s common stock for each $1,000 principal amount of the 2025 Notes which is equivalent to an initial conversion price of approximately $92.12 per share. The conversion rate is subject to adjustment in specified events. The 2025 Notes are convertible into shares of the Company’s common stock, par value $0.001 per share (the “common stock”), at the option of a holder, prior to the close of business on the business day immediately preceding February 15, 2025, only under the following circumstances:

(1) during any calendar quarter commencing after the calendar quarter ending on September 30, 2020 (and only during such calendar quarter), if the last reported sale price of the common stock for at least 20 trading days (whether or not consecutive) during the 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price on each applicable trading day;

(2) during the five consecutive business day period immediately after any five consecutive trading day period (the “measurement period”) in which the “trading price” (as defined in the Indenture) per $1,000 principal amount of the 2025 Notes, as determined following a request by a holder of the 2025 Notes in the manner described in the Indenture, for each trading day of the measurement period was less than 98% of the product of the last reported sale price of the Company’s common stock and the conversion rate on each such trading day;

(3) if the Company calls any or all of the 2025 Notes for redemption, at any time prior to the close of business on the scheduled trading day immediately preceding the redemption date; or

(4) upon the occurrence of certain corporate events specified in the Indenture.

In addition, regardless of the foregoing circumstances, on or after February 15, 2025 until the close of business on the second scheduled trading day immediately preceding the maturity date, a holder may convert all or any portion of its 2025 Notes at any time. Upon conversion, the 2025 Notes may be settled, at the Company’s election, in cash, shares of the Company’s common stock, or a combination of cash and shares of the Company’s common stock in the manner and subject to the terms and conditions provided in the Indenture.

The 2025 Notes are not redeemable at the Company’s option prior to August 20, 2023. The Company may redeem the 2025 Notes for cash, at its option, on a redemption date occurring on or after August 20, 2023, and on or prior to the 41st scheduled trading day immediately preceding the maturity date, if the last reported sale price of the Company’s common stock has been at least 130% of the conversion price then in effect for at least 20 trading days (whether or not consecutive), including the trading day immediately preceding the date on which the Company provides notice of redemption, during any 30 consecutive trading day period ending on and including the trading day immediately preceding the date on which the Company provides notice of redemption at a redemption price equal to 100% of the principal amount of the 2025 Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date.

If the Company undergoes a “fundamental change” (as defined in the Indenture), subject to certain conditions, holders may require the Company to repurchase for cash all or part of their 2025 Notes at a fundamental change repurchase price equal to 100% of the principal amount of the 2025 Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. If the Company is required to repurchase the 2025 Notes due to a fundamental change, it remains at the Company’s discretion to determine whether the settlement is in cash, shares of the Company’s common stock, or a combination of cash and shares of the Company’s common stock.

The Indenture includes customary terms, including certain events of default after which the 2025 Notes may be due and payable immediately. The 2025 Notes are the Company’s unsecured obligations and rank senior in right of payment to all of the Company’s indebtedness that is expressly subordinated in right of payment to the 2025 Notes.

The Company accounted for its convertible senior notes in accordance with ASC 470-20 "Debt with Conversion and Other Options" and separated the Notes into liability and equity components. The carrying amounts of the liability components of the Notes were calculated by measuring the fair value of similar debt instruments that do not have an associated convertible feature. The carrying amounts of the equity components, representing the conversion option, were determined by deducting the fair value of the liability components from the par value of the 2025 Notes. This difference represents the debt discount that is

amortized to interest expense over the terms of the 2025 Notes using the effective interest rate method. The carrying amount of the equity components representing the conversion option was approximately $31,779 for the 2025 Notes and is recorded in additional paid-in capital and are not remeasured as long as they continue to meet the conditions for equity classification.

The Company allocates transaction costs related to the issuance of the 2025 Notes to the liability and equity components using the same proportions as the initial carrying value of the Notes. Transaction costs attributable to the liability component were approximately $6,857 and are being amortized to interest expense at an effective interest method rate of 4.51% over the term of the 2025 Notes. Transaction costs attributable to the equity component were approximately $985 and are netted with the equity component of the 2025 Notes in additional paid-in capital.

The net carrying amount of the liability and equity components of the 2025 Notes as of June 30, 2020 was as follows:

	As of
	June 30, 2020
	(in thousands)
Liability component
Principal	$	253,000
Unamortized discount	(31,138)
Unamortized issuance costs	(6,718)
Net carrying amount	$	215,144
Equity component, net of discount and issuance costs	$	30,794

The interest expense recognized related to the 2025 Notes for the three and six months ended June 30, 2020 was as follows:

	Three Months Ended		Six Months Ended
	June 30, 2020		June 30, 2020
	(in thousands)
Contractual interest expense	$	430	$	430
Amortization of debt discount	641		641
Amortization of debt issuance costs	138		138
Total	$	1,209	$	1,209

As of June 30, 2020, the total estimated fair value of the Notes was approximately $294,001. The fair value was determined based on the closing trading price per $100 of the 2025 Notes as of the last day of trading for the period. The fair value of the Notes is primarily affected by the trading price of our common stock and market interest rates. The fair value of the Notes is considered a Level 2 within the fair value hierarchy and was determined based on inputs that are observable in the market or that could be derived from, or corroborated with, observable market data, quoted price of the Notes in an over-the-counter market.

Capped Call Transactions

On May 6, 2020, in connection with the pricing of the 2025 Notes, the Company entered into privately negotiated capped call transactions (the “Initial Capped Call Transactions”). In addition, in connection with initial purchasers’ exercise in full of their option to purchase additional 2025 Notes, on May 8, 2020, the Company entered into additional privately negotiated capped call transactions (the “Additional Capped Call Transactions,” and, together with the Initial Capped Call Transactions, the “Capped Call Transactions”) with the initial purchasers or their respective affiliates and another financial institution. The capped call transactions are expected generally to reduce the potential dilution to the Company’s common stock upon any conversion of the Notes and/or offset any cash payments the Company is required to make in excess of the principal amount of converted 2025 Notes, as the case may be, with such reduction and/or offset subject to a cap initially equal to $141.72 (which represents a premium of 100% over the last reported sale price of the Company’s common stock on May 6, 2020), subject to certain adjustments.

The Capped Call Transactions are separate transactions, in each case, entered into by the Company with the Option Counterparties, and are not part of the terms of the 2025 Notes and will not change the holders’ rights under the 2025 Notes. As the Capped Call Transactions are considered indexed to the Company's stock and are considered equity classified, they are recorded in stockholders’ equity on the consolidated balance sheet and are not accounted for as derivatives. The cost of the Capped Call Transactions was approximately $29,348 and was recorded as a reduction to additional paid-in capital.