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Derivative Financial Instruments and Fair Value and Credit Risk of Financial Instruments - Additional information (Detail) (USD $) In Millions, unless otherwise specified | 6 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2010 | Dec. 31, 2011 | Jun. 30, 2010
Derivative [Line Items] |  |  |
Unrealized gain, included in Accumulated other comprehensive income/loss |  | $ 0.5 |
Percentage of assets classified within level 3 of fair value hierarchy to total assets and liabilities measured at fair value |  | 1.00% |
Commodity Contract |  |  |
Derivative [Line Items] |  |  |
LME copper prices, average (per ton) | 7,828 | 8,836 | 6,651
LME copper prices, average provisional price (per ton) |  | 8,160 |
Applicable forward copper price |  | 7,643 |
Commodity Contract | Sales |  |  |
Derivative [Line Items] |  |  |
Gain (loss) on mark-to-market value of contracts |  | $ (20.6) |

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- Definition Commodity average price + References No definition available. + Details
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Namespace Prefix: | gfi_
Data Type: | us-types:perUnitItemType
Balance Type: | na
Period Type: | duration

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- Definition Commodity average provisional price + References No definition available. + Details
Name: | gfi_CommodityAverageProvisionalPrice
Namespace Prefix: | gfi_
Data Type: | us-types:perUnitItemType
Balance Type: | na
Period Type: | duration

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- Definition Percentage of unobservable assets to total financial instruments measured at fair value + References No definition available. + Details
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Namespace Prefix: | gfi_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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- Definition The average forward price on the group of price risk forward or futures contracts, such as gas futures contracts. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | us-types:perUnitItemType
Balance Type: | na
Period Type: | instant

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- Definition Net Increase or Decrease in the fair value of the derivative or group of derivatives included in earnings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5618551-113959 + Details
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- Details
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- Definition This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph c(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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258 + Details
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