The number of votes to which a shareholder is entitled.

No definition available.

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- Definition

Ratio representing the net earnings per equivalent common share and dividend and distribution rights of Class B shares to Class A shares.

+ References

No definition available.

+ Details

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- Definition

The number of Class A shares that would be outstanding if all outstanding Class B shares were converted to Class A shares at the conversion rate.

+ References

No definition available.

+ Details

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- Definition

Minimum threshold after repurchase of common stock shares that are held in treasury.

+ References

No definition available.

+ Details

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- Definition

The number of investment shares exchanged in connection with a business acquisition.

+ References

No definition available.

+ Details

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- Definition

The number of shares obtainable from converting one share from one class to another share in another class.

+ References

No definition available.

+ Details

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- Details

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29

-Article 5

+ Details

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- Definition

Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

+ References

+ Details

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

+ Details

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- Definition

Description of share repurchase program, including accounting treatment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23285-112656

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23315-112656

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Balance Type:	na
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- Details

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- Details

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Common stock - Narrative (Detail) (USD $)	12 Months Ended	0 Months Ended	12 Months Ended
Common stock - Narrative (Detail) (USD $)	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2012	Dec. 31, 2013
Class of Stock [Line Items]
Preferred Stock, shares authorized	1,000,000us-gaap_PreferredStockSharesAuthorized
Preferred Stock, shares issued	0us-gaap_PreferredStockSharesIssued
Preferred Stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding
Common Stock Repurchase Program [Member]
Class of Stock [Line Items]
Shares repurchase, authorization description	Berkshire's Board of Directors ("Berkshire's Board") has approved a common stock repurchase program under which Berkshire may repurchase its Class A and Class B shares at prices no higher than a 20% premium over the book value of the shares.
Minimum cash and cash equivalent threshold after repurchase of common stock shares, amount	$ 20,000,000,000
Number of shares acquired	0
WPLG Inc. [Member] \| Graham Holding Company [Member]
Class of Stock [Line Items]
Number of shares exchanged		1,620,190
Class B [Member]
Class of Stock [Line Items]
Ratio of net earnings per equivalent common share and dividend and distribution rights of Class B shares to Class A shares	0.000667
Number of votes entitled per share, number	0.0001
Number of shares of Class B stock obtainable from converting one Class A share	1,500
Number of shares acquired	1,278		606,499
Class B [Member] \| WPLG Inc. [Member]
Class of Stock [Line Items]
Number of shares acquired		1,278
Class A [Member]
Class of Stock [Line Items]
Number of votes entitled per share, number	1
Class A equivalent shares outstanding	1,642,909			1,643,954
Number of shares acquired	2,107		9,475
Class A [Member] \| WPLG Inc. [Member]
Class of Stock [Line Items]
Number of shares acquired		2,107