Strike Price Of Warrants

No definition available.

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Namespace Prefix:	bgc_
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Period Type:	duration

- Definition

Conversion price per share.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Interest rate stated in the contractual debt agreement.

+ 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 Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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

+ Details

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Balance Type:	na
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- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of stock bought back by the entity at the exercise price or redemption price.

+ References

Reference 1: 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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 4, 5

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Equity impact of the value of stock bought back by the entity at the exercise price or redemption price.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount authorized by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Section B

-Paragraph 7

-Subparagraph b

-Chapter 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.

+ Details

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Earnings (Loss) Per Common Share (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	3 Months Ended	6 Months Ended		3 Months Ended	0 Months Ended	3 Months Ended	6 Months Ended
	Nov. 30, 2006 North America [Member] 0.875% Convertible Notes Due 2013 [Member]	Jun. 28, 2013 North America [Member] 0.875% Convertible Notes Due 2013 [Member]	Jun. 28, 2013 North America [Member] 0.875% Convertible Notes Due 2013 [Member]	Dec. 31, 2012 North America [Member] 0.875% Convertible Notes Due 2013 [Member]	Jun. 28, 2013 North America [Member] Subordinated Convertible Notes Due 2029 [Member]	May 15, 2013 Stock Repurchase Program [Member]	Jun. 28, 2013 Stock Repurchase Program [Member]	Jun. 28, 2013 Stock Repurchase Program [Member]
Debt Instrument [Line Items]
Authorized amount						$ 125
Period in force						1 year
Purchase of common shares, value							$ 19.0	$ 19.0
Purchase of common shares, share							579,038	579,038
Average cost per share							$ 32.76	$ 32.76
Interest rate	0.875%	0.875%	0.875%	0.875%
Weighted average conversion price per share		$ 50.36			$ 36.75
Strike price of warrants, per share	$ 76.00		$ 76.00