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Investments - Cash Equivalents and Investments held at Fair Value (Detail) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020 | Jan. 01, 2020
--- | --- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | $ 30,066 | $ 45,116 | $ 37,700
Marketable equity securities | 1,000 | 800 |
Fair Value, Measurements [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Other investments |  | 1,400 |
Total | 70,259 | 82,217 |
Fair Value, Measurements [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Other investments |  | 1,400 |
Total | 52,364 | 46,976 |
Fair Value, Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Total | 17,895 | 34,708 |
Fair Value, Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Total |  | 533 |
Money Market Funds [Member] | Fair Value, Measurements [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Cash equivalents | 652 | 497 |
Money Market Funds [Member] | Fair Value, Measurements [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Cash equivalents | 652 | 497 |
U.S. Government Bonds [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 12,171 | 9,875 |
U.S. Government Bonds [Member] | Fair Value, Measurements [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Cash equivalents |  | 350 |
Available-for-sale debt securities | 12,171 | 9,875 |
U.S. Government Bonds [Member] | Fair Value, Measurements [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Cash equivalents |  | 350 |
Available-for-sale debt securities | 12,171 | 9,875 |
Corporate Bonds [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 10,747 | 11,885 |
Corporate Bonds [Member] | Fair Value, Measurements [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 10,747 | 11,885 |
Corporate Bonds [Member] | Fair Value, Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 10,747 | 11,885 |
Municipal Fixed-Rate Bonds [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 1,551 | 2,884 |
Municipal Fixed-Rate Bonds [Member] | Fair Value, Measurements [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 1,551 | 2,884 |
Municipal Fixed-Rate Bonds [Member] | Fair Value, Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 1,551 | 2,884 |
Asset-Backed Bonds [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 322 | 6,708 |
Asset-Backed Bonds [Member] | Fair Value, Measurements [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 322 | 6,708 |
Asset-Backed Bonds [Member] | Fair Value, Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 322 | 6,708 |
Mortgage/Agency-Backed Bonds [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 4,736 | 11,644 |
Mortgage/Agency-Backed Bonds [Member] | Fair Value, Measurements [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 4,736 | 11,644 |
Mortgage/Agency-Backed Bonds [Member] | Fair Value, Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 4,736 | 11,644 |
Foreign Government Bonds [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 539 | 1,337 |
Foreign Government Bonds [Member] | Fair Value, Measurements [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 539 | 1,337 |
Foreign Government Bonds [Member] | Fair Value, Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities | 539 | 1,337 |
Commercial Paper [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities |  | 250 |
Commercial Paper [Member] | Fair Value, Measurements [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities |  | 250 |
Commercial Paper [Member] | Fair Value, Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities |  | 250 |
Other Investments [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities |  | 533 |
Other Investments [Member] | Fair Value, Measurements [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Marketable equity securities |  | 533 |
Other Investments [Member] | Fair Value, Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale debt securities |  | 533 |
Marketable Equity Securities - Various Industries [Member] | Fair Value, Measurements [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Marketable equity securities | 12,606 | 10,963 |
Marketable Equity Securities - Various Industries [Member] | Fair Value, Measurements [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Marketable equity securities | 12,606 | 10,963 |
Deferred Compensation Plan Assets [Member] | Fair Value, Measurements [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Marketable equity securities | 26,935 | 23,891 |
Deferred Compensation Plan Assets [Member] | Fair Value, Measurements [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Marketable equity securities | $ 26,935 | $ 23,891 |

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