Subsequent Event Subsequent Event (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
VISA, Inc. (VISA) [Member]
Subsequent Event [Line Items]
Investment Owned, Balance, Shares		86,605
Investment Owned, Balance, Principal Amount		$ 0
Forecast [Member]
Subsequent Event [Line Items]
Debt and Equity Securities, Realized Gain (Loss)	$ 17,800,000

For investments which are quantified by principal amount, the principle balance held at close of period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
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-URI http://asc.fasb.org/extlink&oid=99383244&loc=d3e12121-115841

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611133-123010

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