Represents the number of lease agreement entered into by the entity.

No definition available.

Name:	gnc_NumberOfLeaseAgreements
Namespace Prefix:	gnc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the number of shares of common stock owned by related party, as of the balance sheet.

+ References

No definition available.

+ Details

Name:	gnc_NumberOfSharesOfCommonStockHeldByRelatedParty
Namespace Prefix:	gnc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the repurchase price per share under stock repurchase program.

+ References

No definition available.

+ Details

Name:	gnc_StockRepurchaseProgramPricePerShare
Namespace Prefix:	gnc_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Details

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

- Definition

The cash outflow for the obligation for a lease meeting the criteria for capitalization (with maturities exceeding one year or beyond the operating cycle of the entity, if longer).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 26, 31

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3291-108585

+ Details

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

- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

Name:	us-gaap_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

RELATED PARTY TRANSACTIONS (Details) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2012 Cadillac Fairview	Sep. 30, 2013 Cadillac Fairview item	Sep. 30, 2013 Ontrea item	Dec. 31, 2012 OTPP Class A Common Stock Maximum	Dec. 31, 2012 Ares	Aug. 09, 2012 Ares
Related party transaction
Number of lease agreements entered into by the company		16	1
Amount paid under lease agreements	$ 1.9
Number of shares of common stock owned by related party				10,000	0
Number of shares authorized to be repurchased						6,000,000
Repurchase price per share (in dollars per share)						$ 38.42