Percentage of total consolidated net assets exceeded by restricted net assets of the Company's subsidiaries.

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Balance Type:	na
Period Type:	duration

- Definition

Maturity date of the senior notes.

+ Details

Name:	bgc_SeniorNotesDue
Namespace Prefix:	bgc
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Term loan subsidiary minimum net assets.

+ Details

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Namespace Prefix:	bgc
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 21
-Paragraph 16, 20

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

+ Details

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Data Type:	us-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Common stock cash dividend declared by an entity during the period. This element includes paid and unpaid dividends declared during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

+ Details

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Balance Type:	debit
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Supplemental Guarantor and Parent Company Condensed Financial Information (Narrative) (Details)	3 Months Ended	6 Months Ended	12 Months Ended									6 Months Ended
	Jul. 01, 2011 USD ($)	Jul. 01, 2011 EUR (€)	Dec. 31, 2010 USD ($)	Jul. 01, 2011 Parent Company [Member] North America [Member] 0.875% Convertible Note due 2013 [Member] USD ($)	Dec. 31, 2010 Parent Company [Member] North America [Member] 0.875% Convertible Note due 2013 [Member] USD ($)	Jul. 01, 2011 Parent Company [Member] North America [Member] Senior Floating Notes Due In 2015 [Member] USD ($)	Jul. 01, 2011 Parent Company [Member] North America [Member] 1.00% Senior Convertible Notes [Member] USD ($)	Jul. 01, 2011 Parent Company [Member] North America [Member] 7.125% Senior Notes due 2017 [Member] USD ($)	Dec. 31, 2010 Parent Company [Member] North America [Member] 7.125% Senior Notes due 2017 [Member] USD ($)	Jul. 01, 2011 0.875% Convertible Note due 2013 [Member]	Jul. 01, 2011 1.00% Senior Convertible Notes [Member]	Jul. 01, 2011 7.125% Senior Notes due 2017 [Member]	Jul. 01, 2011 Senior Floating Notes Due In 2015 [Member]
Debt principal amount				$ 355,000,000	$ 355,000,000	$ 125,000,000	$ 10,600,000	$ 200,000,000	$ 200,000,000
Interest rate on senior convertible notes										0.875%	1.00%	7.125%
Term loan covenant percentage		25.00%
Senior Notes due												2017	2015
Cash dividend paid	0		0
Term loan subsidiary minimum net assets		€ 197,000,000