Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Assets:
Securities	$ 77,793	$ 89,284
Other assets	23,810	24,505
Fair Value Measurements, Recurring Basis
Assets:
Cash and cash equivalents	85,500	73,200
Total assets measured at fair value	163,271	162,506
Fair Value Measurements, Recurring Basis \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Total assets measured at fair value	74,483	46,149
Fair Value Measurements, Recurring Basis \| Significant Other Observable Inputs (Level 2)
Assets:
Total assets measured at fair value	88,788	116,357
Fair Value Measurements, Recurring Basis \| Significant Unobservable Inputs (Level 3)
Assets:
Total assets measured at fair value	0	0
Fair Value Measurements, Recurring Basis \| Money market funds
Assets:
Cash and cash equivalents	74,483	46,149
Fair Value Measurements, Recurring Basis \| Money market funds \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Cash and cash equivalents	74,483	46,149
Fair Value Measurements, Recurring Basis \| Money market funds \| Significant Other Observable Inputs (Level 2)
Assets:
Cash and cash equivalents	0	0
Fair Value Measurements, Recurring Basis \| Money market funds \| Significant Unobservable Inputs (Level 3)
Assets:
Cash and cash equivalents	0	0
Fair Value Measurements, Recurring Basis \| Government-sponsored enterprises
Assets:
Securities	13,748	13,222
Fair Value Measurements, Recurring Basis \| Government-sponsored enterprises \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Securities	0	0
Fair Value Measurements, Recurring Basis \| Government-sponsored enterprises \| Significant Other Observable Inputs (Level 2)
Assets:
Securities	13,748	13,222
Fair Value Measurements, Recurring Basis \| Government-sponsored enterprises \| Significant Unobservable Inputs (Level 3)
Assets:
Securities	0	0
Fair Value Measurements, Recurring Basis \| Corporate debt securities
Assets:
Securities	75,040	103,135
Fair Value Measurements, Recurring Basis \| Corporate debt securities \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Securities	0	0
Fair Value Measurements, Recurring Basis \| Corporate debt securities \| Significant Other Observable Inputs (Level 2)
Assets:
Securities	75,040	103,135
Fair Value Measurements, Recurring Basis \| Corporate debt securities \| Significant Unobservable Inputs (Level 3)
Assets:
Securities	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of noncurrent assets classified as other.

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