The percentage of investment in reverse repurchase agreements which are collateralized by deposits.

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

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.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- References

No definition available.

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Financial Instruments
Fair value assets, transfers from Level 1 to Level 2	$ 0		$ 0
Fair value assets, transfers from Level 2 to Level 1	0		0
Fair value liabilities, transfers from Level 1 to Level 2	0		0
Fair value liabilities, transfers from Level 2 to Level 1	$ 0		$ 0
Reverse repurchase agreements \| Government Securities and Obligations \| Minimum
Financial Instruments
Percentage of investment amount to collateralized deposits value	102.00%
Recurring
Summary of assets measured at fair value on a recurring basis
Total assets	$ 52,766	$ 33,714
Recurring \| Level 1
Summary of assets measured at fair value on a recurring basis
Total assets	8,624	5,432
Recurring \| Level 2
Summary of assets measured at fair value on a recurring basis
Total assets	44,142	28,282
Recurring \| Money market fund
Summary of assets measured at fair value on a recurring basis
Cash and cash equivalents	8,624	5,432
Recurring \| Money market fund \| Level 1
Summary of assets measured at fair value on a recurring basis
Cash and cash equivalents	8,624	5,432
Recurring \| Commercial Paper
Summary of assets measured at fair value on a recurring basis
Short-term investments		1,993
Recurring \| Commercial Paper \| Level 2
Summary of assets measured at fair value on a recurring basis
Short-term investments		1,993
Recurring \| Corporate debt securities
Summary of assets measured at fair value on a recurring basis
Cash and cash equivalents	2,383	1,937
Short-term investments	7,759	3,352
Recurring \| Corporate debt securities \| Level 2
Summary of assets measured at fair value on a recurring basis
Cash and cash equivalents	2,383	1,937
Short-term investments	7,759	3,352
Recurring \| Reverse repurchase agreements
Summary of assets measured at fair value on a recurring basis
Short-term investments	34,000	21,000
Recurring \| Reverse repurchase agreements \| Level 2
Summary of assets measured at fair value on a recurring basis
Short-term investments	$ 34,000	$ 21,000