Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
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-Name Accounting Standards Codification
-Topic 805
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-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477

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- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

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- Definition

Increase (decrease) in contributed capital due to accretion of noncontrolling interests.

+ References

No definition available.

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- Definition

The minimum percent of Alleghany voting power required for the approval of the merger

+ References

No definition available.

+ Details

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- Definition

Significant accounting policies.

+ References

No definition available.

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Summary of Significant Accounting Principles - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
	Mar. 20, 2022	Mar. 31, 2022	Mar. 31, 2021	Oct. 14, 2021	Oct. 13, 2021
Significant Accounting Policies [Line Items]
Accretion reduced capital contribution		$ 16.5	$ 0.0
Berkshire Hathaway Inc.
Significant Accounting Policies [Line Items]
Par value of common stock issued and outstanding	$ 1.00
Minimum Alleghany voting power required for the approval of the merger	75.00%
Cash offered per share of Alleghany common stock	$ 848.02
Purchase price for acquisition	$ 11,600.0
Kentucky Trailer
Significant Accounting Policies [Line Items]
Ownership of interest held by noncontrolling partners		22.00%
Integrated Project Services LLC
Significant Accounting Policies [Line Items]
Ownership of interest held by noncontrolling partners		18.00%		18.00%	15.00%
Jazwares, LLC
Significant Accounting Policies [Line Items]
Ownership of interest held by noncontrolling partners		24.00%
WWSC Holdings, LLC
Significant Accounting Policies [Line Items]
Ownership of interest held by noncontrolling partners		20.00%
Concord
Significant Accounting Policies [Line Items]
Ownership of interest held by noncontrolling partners		15.00%