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Investments - Contractual Maturities of Debt Securities and Other Investments (Detail) - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021
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Schedule of Available-for-sale Securities [Line Items] |  |
Available-for-sale debt securities, Fair Value/Carrying Value | $ 29,272 | $ 30,066
Corporate Bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Less than one year | 621 |
One to two years | 6,484 |
Two to three years | 3,339 |
Three to five years | 125 |
Available-for-sale debt securities, Fair Value/Carrying Value | 10,569 | 10,747
Municipal Fixed-Rate Bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Less than one year | 148 |
One to two years | 1,254 |
Two to three years | 112 |
Available-for-sale debt securities, Fair Value/Carrying Value | 1,514 | 1,551
Asset-Backed Bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Two to three years | 248 |
Three to five years | 313 |
Five to ten years | 215 |
More than ten years | 227 |
Available-for-sale debt securities, Fair Value/Carrying Value | 1,003 | 322
Mortgage/Agency-Backed Bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Less than one year | 637 |
One to two years | 472 |
Two to three years | 621 |
Three to five years | 189 |
Five to ten years | 925 |
More than ten years | 1,170 |
Available-for-sale debt securities, Fair Value/Carrying Value | 4,014 | 4,736
U.S. Government Bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Less than one year | 367 |
One to two years | 8,315 |
Two to three years | 3,102 |
Available-for-sale debt securities, Fair Value/Carrying Value | 11,784 | 12,171
Foreign Government Bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
One to two years | 279 |
Two to three years | 109 |
Available-for-sale debt securities, Fair Value/Carrying Value | $ 388 | $ 539

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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27198-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3A -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126980459&loc=SL120269850-112803 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
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