STOCKHOLDERS' EQUITY (Outstanding Warrants - Assumptions) (Details) (Warrant [Member])	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Warrant [Member]
Stockholders Equity Note [Line Items]
Expected volatility	63.00%	60.00%
Expected term (in years)	1 year 10 months 24 days	2 years 10 months 24 days
Risk free rate	0.25%	0.36%

Name:	chop_StockholdersEquityNoteLineItems
Namespace Prefix:	chop_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

+ Details

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

- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ References

+ Details

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

- Definition

Risk-free interest rate assumption used in valuing an instrument.

+ References

+ Details

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