Unrealized Losses Related to Marketability of Securities or Issuer's Ability to Honor Redemption Obligations

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- Definition

Number of investment positions in available-for-sale investments that have been in a continuous unrealized loss position for greater than or equal to a year for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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No definition available.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer.

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No definition available.

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- Definition

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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- Definition

Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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- Definition

Balance held at close of period in number of shares.

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Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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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.

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Investments (Narrative) (Details) shares in Thousands	3 Months Ended		9 Months Ended
Investments (Narrative) (Details) shares in Thousands	Sep. 30, 2019 USD ($) investments investment shares	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) investments investment shares	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Schedule of Investments [Line Items]
Available for sale securities, realized gains	$ 1,300,000		$ 7,000,000.0
Available for sale securities, realized loss	190,000.0		190,000
Available for sale securities, realized gain (loss)	$ 1,136,000	$ 0	$ 6,855,000	$ 0
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, number of positions \| investment	108		108
Unrealized losses related to marketability of securities or issuer's ability to honor redemption obligations	$ 0		$ 0
Investment value deemed to be OTTI	0
Investment securities, aggregate carrying value, pledged as collateral	$ 3,400,000,000		$ 3,400,000,000		$ 4,030,000,000.00
Mortgage-backed securities
Schedule of Investments [Line Items]
Available-for-sale, securities in unrealized loss positions, number of positions, greater than or equal to one year \| investments	107		107
Corporate Bonds
Schedule of Investments [Line Items]
Available-for-sale, securities in unrealized loss positions, number of positions, greater than or equal to one year \| investments	1		1
Visa Class B Common Stock
Schedule of Investments [Line Items]
Investment owned (in shares) \| shares	298		298
Investment owned, fair value	$ 0		$ 0