Value of all classes of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares exclude common shares repurchased by the entity and held as treasury shares.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 30
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13537-108611

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13531-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

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- Definition

The percentage of the fair value of equity securities to the fair value of total plan assets held as of the measurement date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2446-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

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Target allocation maximum percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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Target allocation maximum percentage in other than debt securities, equity securities, and real estate to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 7
-Section 03
-Paragraph 1
-Subparagraph h

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(h))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Obligation(s) resulting from employer withdrawal from a multiemployer 1) pension plan under circumstances that would give rise to an obligation or (b) other postretirement benefit plan under circumstances that would give rise to an obligation or an increase in the contribution to the fund during the remainder of the contract period to make up a shortfall necessary to fund the vested and negotiated benefits.

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Pension and Postretirement Plans (Narrative) (Details) (USD $)	3 Months Ended	6 Months Ended				6 Months Ended		6 Months Ended			6 Months Ended
	Jul. 04, 2010	Jul. 03, 2011	Jul. 04, 2010	Jun. 30, 2011 International Stocks [Member]	Dec. 31, 2010 International Stocks [Member]	Jul. 03, 2011 International Stocks [Member] Pension Plans [Member]	Jun. 30, 2011 Foreign Investments [Member]	Jul. 03, 2011 Pension Plans [Member] Berkshire Hathaway [Member]	Jun. 30, 2011 Pension Plans [Member] Berkshire Hathaway Class A and B [Member]	Dec. 31, 2010 Pension Plans [Member] Berkshire Hathaway Class A and B [Member]	Jul. 03, 2011 Pension Plans [Member]	Jun. 30, 2011 Pension Plans [Member]	Mar. 31, 2011 Pension Plans [Member]	Dec. 31, 2010 Pension Plans [Member]	Jun. 30, 2011 Foreign Pension Plans [Member]	Dec. 31, 2010 Foreign Pension Plans [Member]
Defined benefit plan, target allocation percentage of assets, equity securities, range maximum						24.00%		20.00%
Defined benefit plan, target allocation percentage of assets, other, range maximum											10.00%
Minimum percentage of plan assets considered as significant concentrations in pension plans													10.00%
Common stock									$ 155,800,000	$ 161,600,000
Value of investments							270,700,000					247,500,000		134,800,000		155,000,000
Defined Benefit Plan, Equity Securities				23.00%	15.00%							14.00%		8.00%	15.00%	9.00%
Multiemployer pension plan withdrawal charge	$ 17,700,000		$ 17,700,000