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Commitments and Contingencies - Additional Information (Detail) |  |  | 6 Months Ended |
--- | --- | --- | --- | ---
Mar. 31, 2020 Officer | Oct. 17, 2019 Officer | Jun. 30, 2020 USD ($) | Dec. 31, 2019 USD ($)
Contingencies And Commitments [Line Items] |  |  |  |
Commitments related to performance bonds |  |  | $ 11,300,000 | $ 9,300,000
Commitments related to performance bonds expiration month and year |  |  | 2024-08 |
Letter of credit secured by pledge of collateral amount |  |  | $ 5,000,000.0 |
Commitments towards private equity funds |  |  | 4,900,000 |
Investment Commitments [Member] |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |
Aggregate investment committed in private equity funds |  |  | 5,000,000.0 |
Restricted Cash |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |
Letter of credit secured by pledge of collateral amount |  |  | 1,200,000 |
Long-term Investments [Member] |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |
Letter of credit secured by pledge of collateral amount |  |  | 3,800,000 |
Minimum [Member] |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |
Collateral value required to be maintained |  |  | 5,000,000.0 |
Maximum [Member] |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |
Collateral value required to be maintained |  |  | $ 12,000,000.0 |
Current Executive Officers [Member] |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |
Number of officers | Officer | 2 | 2 |  |
Former Executive Officers [Member] |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |
Number of officers | Officer | 1 | 1 |  |

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- Definition Commitments related to performance bonds. + References No definition available. + Details
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- Definition Commitments related to performance bonds expiration month and year. + References No definition available. + Details
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- Definition Amount of contributions made that have been applied to private equity fund commitments. + References No definition available. + Details
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- Definition Letter of credit secured by pledge of collateral. + References No definition available. + Details
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- Definition Amount of assets pledged to secure a debt instrument. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 + Details
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- Definition Cost of the investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=99383244&loc=d3e12121-115841 + Details
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- Details
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