The period of service required for eligibility for full time employees for matching contributions by the employer.

No definition available.

Name:	gnc_DefinedContributionPlanEligiblePeriodOfServiceForFullTimeEmployeesForMatchingContribution
Namespace Prefix:	gnc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The period of service required for eligibility for part time employees for matching contributions by the employer.

+ References

No definition available.

+ Details

Name:	gnc_DefinedContributionPlanEligiblePeriodOfServiceForPartTimeEmployeesForMatchingContribution
Namespace Prefix:	gnc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of deferral compensation by the employee to a defined contribution plan.

+ References

No definition available.

+ Details

Name:	gnc_DefinedContributionPlanEmployeeContributionDeferralPercentage
Namespace Prefix:	gnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

Name:	gnc_DefinedContributionPlanEmployerDiscretionaryContributionPercentage
Namespace Prefix:	gnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of contribution that can be made by employee.

+ References

No definition available.

+ Details

Name:	gnc_DefinedContributionPlanPercentageOfEmployeeContributions
Namespace Prefix:	gnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the years of service that an employee has to complete to become eligible to participate in plan.

+ References

No definition available.

+ Details

Name:	gnc_DefinedContributionPlanYearsOfService
Namespace Prefix:	gnc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

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

- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph g

-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

Name:	us-gaap_DefinedBenefitPlanEstimatedFutureEmployerContributionsInNextFiscalYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 11

-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

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

- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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

- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployersMatchingContributionAnnualVestingPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum percentage of employee gross pay, by the terms of the plan, that the employer may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanMaximumAnnualContributionPerEmployeePercent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

RETIREMENT PLANS (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended		12 Months Ended
	Feb. 28, 2013	Feb. 28, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Retirement plans
Eligibility for matching contribution for full time employees, period of service			30 days
Eligibility for matching contribution for part time employees, period of service			1000 hours
Employer match of employee contributions of first 3% of eligible compensation (as a percent)			50.00%
Percentage of eligible compensation, matched 50% by employer			3.00%
Percentage of discretionary contribution made by employer			50.00%
Percentage of deferral salary contributed by employee			3.00%
Cash contribution made			$ 1.6	$ 1.5	$ 1.3
Discretionary match amount	1.5	1.3
Cash contributions for next fiscal year			$ 0.8
0-1
Retirement plans
Percent Vested			0.00%
1-2
Retirement plans
Percent Vested			33.00%
2-3
Retirement plans
Percent Vested			66.00%
3+
Retirement plans
Percent Vested			100.00%
Minimum
Retirement plans
Employee contributions (as a percent)			1.00%
Minimum \| 0-1
Retirement plans
Years of Service			0 years
Minimum \| 1-2
Retirement plans
Years of Service			1 year
Minimum \| 2-3
Retirement plans
Years of Service			2 years
Minimum \| 3+
Retirement plans
Years of Service			3 years
Maximum
Retirement plans
Employee contributions (as a percent)			80.00%
Maximum \| 0-1
Retirement plans
Years of Service			1 year
Maximum \| 1-2
Retirement plans
Years of Service			2 years
Maximum \| 2-3
Retirement plans
Years of Service			3 years