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Summary of Significant Accounting Polices - Fair Value of Financial Instruments (Details) | 12 Months Ended
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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%

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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 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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