Redeemable Non-controlling Interest (Narrative) (Details) (ProCables S.A. [Member], Rest of World [Member])	0 Months Ended
Oct. 01, 2012
Redeemable Noncontrolling Interest [Line Items]
Percentage of interests acquired	60.00%
Term after no-transfer period that shareholders' may exercise	36 months
Percentage of voting interests to be purchased	40.00%
Seller [Member]
Redeemable Noncontrolling Interest [Line Items]
Noncontrolling interest, ownership percentage	40.00%
Ownership percentage by parent	40.00%

Business Acquisition, Percentage of Voting Interests to be Purchased

No definition available.

Name:	bgc_BusinessAcquisitionPercentageofVotingIntereststobePurchased
Namespace Prefix:	bgc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Term after No-transfer Period That Shareholders may Exercise

+ References

No definition available.

+ Details

Name:	bgc_TermAfterNoTransferPeriodThatShareholdersMayExercise
Namespace Prefix:	bgc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_RedeemableNoncontrollingInterestLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration