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

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-Publisher FASB
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

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The net cash inflow or outflow for the increase (decrease) associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=109979856&loc=SL6284422-111562

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Cash and Marketable Securities - Additional Information (Detail) - USD ($)	1 Months Ended	9 Months Ended		12 Months Ended
	Oct. 31, 2019	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Subsequent Event [Line Items]
Letter of credit established as a deposit		$ 3,500,000
Realized losses of available-for-sale securities		0	$ 0
Other-than-temporarily impaired investments		$ 0		$ 0
Subsequent Event
Subsequent Event [Line Items]
Release of restricted cash	$ 2,000,000.0