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Commitments, contingencies, and guarantees Commitments, Contingencies, And Gaurentees (Letter of Credit Narrative) - USD ($) $ in Billions | Oct. 31, 2017 | Oct. 25, 2017 | Sep. 30, 2017
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Line of Credit Facility [Line Items] |  |  |
Other Investments Limited Partnerships And Partially Owned Investment Companies Funding Commitments |  |  | $ 1.7
Line of Credit Facility, Current Borrowing Capacity |  |  | $ 1.5
Subsequent Event [Member] |  |  |
Line of Credit Facility [Line Items] |  |  |
Other Investments Limited Partnerships And Partially Owned Investment Companies Funding Commitments | $ 2.5 |  |
Line of Credit Facility, Maximum Borrowing Capacity |  | $ 2.0 |
Line of Credit Facility, Current Borrowing Capacity |  | 1.0 |
Line of Credit Facility, Capacity Available for Specific Purpose Other than for Trade Purchases |  | $ 1.0 |

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- Definition Funding commitments relating to limited partnerships and partially-owned investment companies included in other investments. + References No definition available. + Details
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- Definition The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer. + References No definition available. + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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