Debt	12 Months Ended
Dec. 31, 2020
Debt [Abstract]
Debt	13. Debt On May 8, 2020, we entered into a $600,000 revolving credit facility with JPMorgan Chase Bank as administrative agent, which expires on May 7, 2021. We pay a commitment fee of 0.625% per year for unused amounts under the credit facility. Interest on borrowings currently bear interest at a rate equal to the London Interbank Offered Rate (LIBOR) plus 1.50%, which may increase due to changes in our total leverage ratio as defined in the credit agreement. Further, we are subject to certain covenants, which include (i) maintaining a total leverage ratio of less than 3.0x, (ii) maintaining a consolidated fixed charge coverage ratio of greater than 1.5x and (iii) limiting us from making investments and capital expenditures in certain circumstances. We had no outstanding borrowings under the credit facility as of December 31, 2020.

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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