2.2.0.7 false Condensed Consolidated Balance Sheet (Unaudited) (Parenthetical) (USD $) 0121 - Statement - Condensed Consolidated Balance Sheet (Unaudited) (Parenthetical) true false In Millions, except Share data false false 1 USD false false Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 $ false 2 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ 3 Current Assets 1 us-gaap_AssetsCurrentAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 4 Allowances for doubtful receivables 2 us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 true true false false 17200000 17.2 false false false 2 true true false false 18000000 18.0 false false false xbrli:monetaryItemType monetary A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 4 -Article 5 false 5 Shareholders' Equity 1 us-gaap_StockholdersEquityAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 6 Common stock, par value 2 us-gaap_CommonStockParOrStatedValuePerShare us-gaap true na instant No definition available. false false false false false false false false false false false verboselabel true 1 true true false false 5 5 false false false 2 true true false false 5 5 false false false us-types:perShareItemType decimal Face amount or stated value of common stock per share; generally not indicative of the fair market value per share. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 false 7 Common stock, shares authorized 2 us-gaap_CommonStockSharesAuthorized us-gaap true na instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 200000000 200000000 false false false 2 false true false false 200000000 200000000 false false false xbrli:sharesItemType shares The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 false 8 Common stock, shares issued 2 gr_CommonStockIssued gr false na instant Total number of common shares of an entity that have been sold or granted to shareholders (excludes common shares that have... false false false false false false false false false false false verboselabel false 1 false true false false 147233266 147233266 false false false 2 false true false false 145241995 145241995 false false false xbrli:sharesItemType shares Total number of common shares of an entity that have been sold or granted to shareholders (excludes common shares that have been repurchased). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued includes shares outstanding but excludes shares held in treasury. No authoritative reference available. false 9 Common stock, excluding shares held by a wholly owned subsidiary 2 gr_CommonStockSharesHeldByWhollyOwnedSubsidiary gr false na instant Common stock, shares held by wholly owned subsidiary. false false false false false false false false false false false verboselabel false 1 false true false false 14000000 14000000 false false false 2 false true false false 14000000 14000000 false false false xbrli:sharesItemType shares Common stock, shares held by wholly owned subsidiary. No authoritative reference available. false 10 Common stock held in treasury, shares 2 us-gaap_TreasuryStockShares us-gaap true na instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 21950768 21950768 false false false 2 false true false false 20854137 20854137 false false false xbrli:sharesItemType shares Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 false 2 8 false HundredThousands NoRounding NoRounding false true