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v3.20.4

Investments - Summary of Available for Sale Securities (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Total |  |
Total, amortized cost | $ 10,806 | $ 10,679
Total, gross unrealized gains | 2,320 | 2,837
Total, gross unrealized losses | (63) | (53)
Total, estimated fair value | 13,063 | 13,463
Equities |  |
Equity securities |  |
Equity securities, amortized cost | 172 | 417
Equity securities, gross unrealized gains | 628 | 1,755
Equity securities, gross unrealized losses | 0 | 0
Equity securities, estimated fair value | 800 | 2,172
Mutual funds |  |
Equity securities |  |
Equity securities, amortized cost | 5,323 | 4,988
Equity securities, gross unrealized gains | 1,432 | 697
Equity securities, gross unrealized losses | 0 | 0
Equity securities, estimated fair value | 6,755 | 5,685
U.S. Government and agency securities |  |
Available-for-sale securities |  |
Available-for-sale securities, amortized cost | 2,317 | 2,039
Available-for-sale securities, gross unrealized gains | 1 | 5
Available-for-sale securities, gross unrealized losses | (4) | 0
Available-for-sale securities, estimated fair value | 2,314 | 2,044
Corporate bonds |  |
Available-for-sale securities |  |
Available-for-sale securities, amortized cost | 2,879 | 3,103
Available-for-sale securities, gross unrealized gains | 259 | 380
Available-for-sale securities, gross unrealized losses | (6) | 0
Available-for-sale securities, estimated fair value | 3,132 | 3,483
Asset-backed securities and collateralized mortgage obligations |  |
Available-for-sale securities |  |
Available-for-sale securities, amortized cost | 115 | 132
Available-for-sale securities, gross unrealized gains | 0 | 0
Available-for-sale securities, gross unrealized losses | (53) | (53)
Available-for-sale securities, estimated fair value | $ 62 | $ 79

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