Credit Agreement	3 Months Ended
Mar. 31, 2019
Debt Disclosure [Abstract]
Credit Agreement	11. Credit Agreement Line of Credit In September 2015, we entered into a two-year unsecured line of credit agreement (the “Credit Agreement”) with JPMorgan Chase Bank, N.A. (the “Bank”) in the principal amount of up to $12.0 million. In September 2016, the Credit Agreement was modified to extend the final due date to September 2018, at which point it expired. No borrowings were ever outstanding under the Credit Agreement.

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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