Summary of Significant Accounting Polices - Fair Value of Financial Instruments (Details)	12 Months Ended
Dec. 31, 2019 USD ($)
Fair Value of Financial Instruments
Fair value assets, transfers from Level 1 to Level 2	$ 0
Fair value assets, transfers from Level 2 to Level 1	0
Fair value liabilities, transfers from Level 1 to Level 2	0
Fair value liabilities, transfers from Level 2 to Level 1	$ 0
Reverse repurchase agreements \| Government Securities and Obligations \| Minimum
Fair Value of Financial Instruments
Percentage of investment amount to collateralized deposits value	102.00%

The percentage of investment in reverse repurchase agreements which are collateralized by deposits.

No definition available.

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

+ Details

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

+ Details

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

+ Details

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- References

No definition available.

+ Details

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- Details

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- Details

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