Commitments and Contingencies Commitements and Contingencies (Narrative) (Details) $ / shares in Units, $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($) $ / shares shares
VISA Class B Conversion Ratio	1.6298
Common Class B [Member] \| VISA, Inc. (VISA) [Member]
Investment Owned, Balance, Shares \| shares	86,605
Common Class A [Member] \| VISA, Inc. (VISA) [Member]
Share Price \| $ / shares	$ 173.55
Investment Owned, at Fair Value \| $	$ 24.5

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant