Information with Respect to Class A Common Shares that were Surrendered or Repurchased (Detail) - USD ($)	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023
Equity, Class of Treasury Stock [Line Items]
Approximate Dollar Value of Shares that May Yet Be Purchased Under the Plans or Programs	$ 101,000,000
Class A Common Shares
Equity, Class of Treasury Stock [Line Items]
Shares repurchased	16,527	468,860
Average Price Paid Per Share	$ 32	$ 27.04
January 1-31, 2023 \| Employee \| Class A Common Shares
Equity, Class of Treasury Stock [Line Items]
Shares repurchased		3,302
Average Price Paid Per Share		$ 23.31
Total Number of Shares Purchased as Part of Publicly Announced Plan or Program		0
Approximate Dollar Value of Shares that May Yet Be Purchased Under the Plans or Programs		$ 0
January 1-31, 2023 \| Share Repurchase Program \| Class A Common Shares
Equity, Class of Treasury Stock [Line Items]
Shares repurchased		250,000
Average Price Paid Per Share		$ 25.9
Total Number of Shares Purchased as Part of Publicly Announced Plan or Program		250,000
Approximate Dollar Value of Shares that May Yet Be Purchased Under the Plans or Programs		$ 106,604,000
June 1-30, 2024 \| Employee \| Class A Common Shares
Equity, Class of Treasury Stock [Line Items]
Shares repurchased	16,527
Average Price Paid Per Share	$ 32
Total Number of Shares Purchased as Part of Publicly Announced Plan or Program	0
Approximate Dollar Value of Shares that May Yet Be Purchased Under the Plans or Programs	$ 101,004,000
April 1-30, 2023 \| Share Repurchase Program \| Class A Common Shares
Equity, Class of Treasury Stock [Line Items]
Shares repurchased		200,000
Average Price Paid Per Share		$ 28
Total Number of Shares Purchased as Part of Publicly Announced Plan or Program		200,000
Approximate Dollar Value of Shares that May Yet Be Purchased Under the Plans or Programs		$ 101,004,000
June 1-30, 2023 \| Employee \| Class A Common Shares
Equity, Class of Treasury Stock [Line Items]
Shares repurchased		15,558
Average Price Paid Per Share		$ 33.74
Total Number of Shares Purchased as Part of Publicly Announced Plan or Program		0
Approximate Dollar Value of Shares that May Yet Be Purchased Under the Plans or Programs		$ 101,004,000

Number Of Shares Purchased As Part Of Publicly Announced Plan

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Amount remaining authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

+ References

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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-SubTopic 10
-Topic 505
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481549/505-30-45-1

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