Investments - Summary of Proceeds Received and The Gross Realized Gains and Losses From Sales of Equity Securities (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Debt and Equity Securities, FV-NI [Line Items]
Proceeds			$ 12,455	$ 32,841
Equity Securities [Member]
Debt and Equity Securities, FV-NI [Line Items]
Proceeds	$ 3,448	$ 4,967	12,455	32,841
Gross Realized Gains	184	113	969	2,187
Gross Realized Losses	$ (176)	$ (246)	$ (2,932)	$ (2,776)

The cash inflow associated with the sale of equity securities measured at fair value with change in fair value recognized in net income.

No definition available.

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- Definition

Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117546-209714

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- Definition

Amount of realized loss from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

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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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