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v3.21.1

Fair Value Information - Schedule of Percentage Decrease in Discount for Lack of Marketability or Noncontrolling Interests Discount (Detail) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Top of Range [Member] |  |
Disclosure of fair value measurement of assets and liabilities [Line Items] |  |
Discount for lack of marketability | 20.00% | 20.00%
Noncontrolling interests discount | 25.00% | 25.00%
Bottom of Range [Member] |  |
Disclosure of fair value measurement of assets and liabilities [Line Items] |  |
Discount for lack of marketability | 14.73% | 13.73%
Noncontrolling interests discount | 17.29% | 21.45%

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- Definition Disclosure of fair value measurement of assets and liabilities. + References No definition available. + Details
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- Definition Discount rate of noncontrolling interests. + References No definition available. + Details
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Period Type: | duration

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- Definition Percentage of discount for lack of marketability. + References No definition available. + Details
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- Details
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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |