Convertible Senior Notes and Capped Call Transactions

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Abstract]

Convertible Senior Notes and Capped Call Transactions

CONVERTIBLE SENIOR NOTES AND CAPPED CALL TRANSACTIONS

On May 11, 2020, the Company issued the 2025 Notes pursuant to an Indenture dated May 11, 2020 (the “Indenture”). The offering totaled $253,000 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 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, at a rate of 1.25% per year.

The initial conversion rate for the 2025 Notes is 32.5668 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 $30.71 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, at the option of a holder, prior to the close of business on the business day immediately preceding February 15, 2025, under certain conditions.

In addition, on or after February 15, 2025, a holder may convert all or any portion of its 2025 Notes at any time. During the three months ended December 31, 2023, the conversion feature of the 2025 Notes was triggered and therefore the 2025 Notes are currently convertible, in whole or in part, at the option of the holders from January 1, 2024 through March 31, 2024. Whether the 2025 Notes will be convertible following such period will depend on the continued satisfaction of this condition or another conversion condition. The Company has not received any conversion notices through the issuance date of our consolidated financial statements. Since the Company may elect to repay the 2025 Notes in cash, shares of our common stock, or a combination of both, it has continued to classify the 2025 Notes as long-term debt on its consolidated balance sheet as of December 31, 2023.

Effective August 20, 2023, the Company may redeem the 2025 Notes for cash, at its option, subject to the terms and conditions provided in the Indenture.

Prior to the adoption of ASU 2020-06 on January 1, 2022, the Company separated the 2025 Notes into liability and equity components. Following the adoption of ASU 2020-06 on January 1, 2022, which the Company elected to adopt using a modified retrospective approach, the Company no longer separates the 2025 Notes into liability and equity components. The cumulative effect of the accounting change as of January 1, 2022 was a decrease to accumulated deficit of $8,647, a decrease in additional paid-in capital of $30,794 and an increase in liabilities of $22,147 on its consolidated balance sheets. Comparative prior year periods were not adjusted. In connection with the adoption, the Company calculated an effective interest rate of 1.87%.

The net carrying amount of the 2025 Notes was as follows (in thousands):

	December 31, 2023
Liability
Principal	$	253,000
Unamortized issuance costs	(2,523)
Net carrying amount	$	250,477

The interest expense recognized related to the 2025 Notes for the years ended December 31, 2023, 2022 and 2021 was as follows (in thousands):

	Year ended December 31,
	2023		2022		2021
Contractual interest expense	$	3,163	$	3,162	$	3,162
Amortization of debt discount	—		—		5,651
Amortization of debt issuance costs	1,514		1,486		1,219
Total	$	4,677	$	4,648	$	10,032

As of December 31, 2023 and 2022, the total estimated fair value of the 2025 Notes was approximately $386,201 and $260,749, respectively. 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 2025 Notes is primarily affected by the trading price of our common stock and market interest rates. The fair value of the 2025 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 2025 Notes in an over-the-counter market.

Capped Call Transactions

In May 2020, in connection with the pricing of the 2025 Notes, the Company entered into privately negotiated capped call transactions (the “Capped Call Transactions”). The Capped Call Transactions are generally expected to reduce the potential dilution to the Company’s common stock upon any conversion of the 2025 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 $47.24 (the "Cap Price").

The Capped Call Transactions are separate transactions 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 in 2020.