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Fair Value Information - Schedule of Percentage Decrease in Discount for Lack of Marketability or Noncontrolling Interests Discount (Detail)	12 Months Ended
	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%

X

- Definition

Disclosure of fair value measurement of assets and liabilities.

+ References

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- Definition

Discount rate of noncontrolling interests.

+ References

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X

- Definition

Percentage of discount for lack of marketability.

+ References

No definition available.

+ Details

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- Details

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