v3.21.2

Investments - Restricted Cash and Cash Equivalents and Investments (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020 | Jun. 30, 2020
--- | --- | --- | ---
Restricted Cash and Investments Items [Line Items] |  |  |
Restricted cash | $ 31,648 | $ 61,786 | $ 80,870
Restricted investments | 791,489 | 1,018,269 |
Restricted cash and investments | 823,137 | 1,080,055 |
Third Party Agreements |  |  |
Restricted Cash and Investments Items [Line Items] |  |  |
Restricted cash | 20,425 | 20,547 |
Restricted investments | 62,560 | 63,281 |
Amortized cost | 62,589 | 63,253 |
Related Party Agreements |  |  |
Restricted Cash and Investments Items [Line Items] |  |  |
Restricted cash | 11,223 | 41,239 |
Restricted investments | 765,144 | 954,988 |
Amortized cost | 742,157 | 913,466 |
Related Party Agreements, Liability For Investments Purchased |  |  |
Restricted Cash and Investments Items [Line Items] |  |  |
Restricted investments | $ (36,215) | $ 0 |

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- Definition Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(2)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=123431023&loc=SL98516268-108586 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(1)(a)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3044-108585 + Details
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