Long-Term Debt (Schedule of Europe and Mediterranean Uncommitted Accounts Receivable Facilities) (Details) (Europe and Mediterranean [Member], USD $) In Millions, unless otherwise specified	6 Months Ended	12 Months Ended
Jul. 01, 2011	Dec. 31, 2010
Outstanding borrowings	$ 29.1	$ 38.1
Undrawn availability	114.5	125.4
Interest rate - weighted average	5.00%	3.10%
Uncommitted Accounts Receivable Facilities [Member]
Outstanding borrowings	4.2
Undrawn availability	$ 82.6	$ 113.7
Interest rate - weighted average	2.10%
Maturity date	Various	Various

Reflects the calculation as of the balance sheet date of the average interest rate weighted by the amount of debt outstanding by type or by instrument at that time.

Name:	bgc_DebtWeightedAverageInterestRate
Namespace Prefix:	bgc
Data Type:	us-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 129
-Paragraph 2, 4

+ Details

Name:	us-gaap_DebtInstrumentMaturityDateDescription
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount borrowed under the credit facility as of the balance-sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 22
-Article 5

+ Details

Name:	us-gaap_LineOfCreditFacilityAmountOutstanding
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 22
-Article 5

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant