Convertible 4.5% Senior Notes	9 Months Ended
Sep. 30, 2021
Convertible 4.5% Senior Notes
Convertible 4.5% Senior Notes	D.Convertible 4.5% Senior Notes In 2016, the Company issued convertible notes with an aggregate principal amount of $100.0 million, of which $2.1 million remained outstanding as of December 31, 2020. In June 2021, $1.0 million of outstanding convertible notes were converted into 238,777 shares of the Company’s common stock and the remaining $1.1 million outstanding was repaid in full by a cash payment upon maturity on July 1, 2021. The convertible notes were senior unsecured obligations with an interest rate of 4.5% per year, paid semi-annually in arrears on January 1 and July 1 of each year, commencing on January 1, 2017. The Company recorded $47,000 and $71,000 of interest expense for the nine months ended September 30, 2021 and 2020, respectively. The Company analyzed the terms of the convertible notes and determined that under current accounting guidance the notes were entirely accounted for as debt, and none of the terms of the notes required separate accounting.

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-URI http://asc.fasb.org/topic&trid=2208564

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