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Fair Value Measurements (Narrative) (Details) - Recurring [Member] | Sep. 30, 2019 USD ($) shares
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items] |
Transfers of assets and liabilities between levels | $ | $ 0
Visa Inc [Member] |
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items] |
Number of shares of Visa Class B common stock | shares | 192,163
Investment Securities [Member] | Minimum [Member] |
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items] |
Targeted duration | 2 years
Investment Securities [Member] | Maximum [Member] |
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items] |
Targeted duration | 5 years 6 months

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- Definition Fair Value, Equity Between Levels One Two Three Transfers, Amount + References No definition available. + Details
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- Definition Period between issuance and maturity of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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