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v3.23.3

Investments, Summary of Investments (Details) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2023 USD ($) Company | Dec. 31, 2022 USD ($)
Ownership Interests in Private and Public Companies [Abstract] |  |  |
Number of private companies in which there is an equity ownership interest of less than 20% | Company |  | 7 |
Number of public companies in which there is an equity ownership interest of less than 20% | Company |  | 3 |
Available-for-sale Debt Securities with Maturity of One Year or Less [Abstract] |  |  |
Amortized cost |  | $ 1,346,830 | $ 1,223,522
Gross unrealized gains |  | 14 | 64
Gross unrealized losses |  | (9,190) | (12,018)
Estimated fair value |  | 1,337,654 | 1,211,568
Available-for-sale Debt Securities with Maturity of More Than One Year [Abstract] |  |  |
Amortized cost |  | 553,704 | 525,314
Gross unrealized gains |  | 236 | 130
Gross unrealized losses |  | (7,082) | (15,621)
Estimated fair value |  | 546,858 | 509,823
Available-for-sale Debt Securities [Abstract] |  |  |
Amortized cost |  | 1,900,534 | 1,748,836
Gross unrealized gains |  | 250 | 194
Gross unrealized losses |  | (16,272) | (27,639)
Estimated fair value |  | 1,884,512 | 1,721,391
Equity Securities [Abstract] |  |  |
Amortized cost |  | 35,012 | 35,012
Gross unrealized gains |  | 23,749 | 17,257
Gross unrealized losses |  | (9,208) | (1,358)
Estimated fair value |  | 49,553 | 50,911
Available-for-sale Debt and Equity Securities [Abstract] |  |  |
Amortized cost |  | 1,935,546 | 1,783,848
Gross unrealized gains |  | 23,999 | 17,451
Gross unrealized losses |  | (25,480) | (28,997)
Estimated fair value |  | 1,934,065 | 1,772,302
Corporate Debt Securities [Member] |  |  |
Available-for-sale Debt Securities with Maturity of One Year or Less [Abstract] |  |  |
Amortized cost | [1] | 535,408 | 513,790
Gross unrealized gains |  | 13 | 23
Gross unrealized losses |  | (4,492) | (4,365)
Estimated fair value |  | 530,929 | 509,448
Available-for-sale Debt Securities with Maturity of More Than One Year [Abstract] |  |  |
Amortized cost |  | 195,674 | 227,631
Gross unrealized gains |  | 183 | 14
Gross unrealized losses |  | (3,160) | (10,143)
Estimated fair value |  | 192,697 | 217,502
Debt Securities Issued by U.S. Government Agencies [Member] |  |  |
Available-for-sale Debt Securities with Maturity of One Year or Less [Abstract] |  |  |
Amortized cost |  | 267,503 | 133,585
Gross unrealized gains |  | 0 | 0
Gross unrealized losses |  | (1,429) | (1,829)
Estimated fair value |  | 266,074 | 131,756
Available-for-sale Debt Securities with Maturity of More Than One Year [Abstract] |  |  |
Amortized cost |  | 56,365 | 34,339
Gross unrealized gains |  | 0 | 0
Gross unrealized losses |  | (507) | (1,040)
Estimated fair value |  | 55,858 | 33,299
Debt Securities Issued by the U.S. Treasury [Member] |  |  |
Available-for-sale Debt Securities with Maturity of One Year or Less [Abstract] |  |  |
Amortized cost | [1] | 520,013 | 512,655
Gross unrealized gains |  | 1 | 23
Gross unrealized losses |  | (3,027) | (5,124)
Estimated fair value |  | 516,987 | 507,554
Available-for-sale Debt Securities with Maturity of More Than One Year [Abstract] |  |  |
Amortized cost |  | 297,501 | 245,030
Gross unrealized gains |  | 0 | 0
Gross unrealized losses |  | (3,364) | (4,109)
Estimated fair value |  | 294,137 | 240,921
Debt Securities Issued by States of the U.S. and Political Subdivisions of the States [Member] |  |  |
Available-for-sale Debt Securities with Maturity of One Year or Less [Abstract] |  |  |
Amortized cost |  | 23,906 | 57,484
Gross unrealized gains |  | 0 | 18
Gross unrealized losses |  | (242) | (686)
Estimated fair value |  | 23,664 | 56,816
Available-for-sale Debt Securities with Maturity of More Than One Year [Abstract] |  |  |
Amortized cost |  | 4,164 | 18,314
Gross unrealized gains |  | 53 | 116
Gross unrealized losses |  | (51) | (329)
Estimated fair value |  | 4,166 | 18,101
Other Municipal Debt Securities [Member] |  |  |
Available-for-sale Debt Securities with Maturity of One Year or Less [Abstract] |  |  |
Amortized cost |  |  | 6,008
Gross unrealized gains |  |  | 0
Gross unrealized losses |  |  | (14)
Estimated fair value |  |  | 5,994
Publicly Traded Equity Securities [Member] |  |  |
Equity Securities [Abstract] |  |  |
Amortized cost | [2] | 11,897 | 11,897
Gross unrealized gains |  | (1,252) | 0
Gross unrealized losses |  | (4,083) | (1,358)
Estimated fair value |  | 6,562 | 10,539
Available-for-sale Debt and Equity Securities [Abstract] |  |  |
Unrealized loss on equity securities |  | (4,000) |
Privately Held Equity Securities [Member] |  |  |
Equity Securities [Abstract] |  |  |
Amortized cost | [3] | 23,115 | 23,115
Gross unrealized gains |  | 25,001 | 17,257
Gross unrealized losses |  | (5,125) | 0
Estimated fair value |  | 42,991 | $ 40,372
Available-for-sale Debt and Equity Securities [Abstract] |  |  |
Unrealized gain on equity securities |  | $ 2,600 |
[1] | Includes investments classified as cash equivalents in our condensed consolidated balance sheets.
[2] | Our publicly traded equity securities are included in other current assets. We recognize publicly traded equity securities at fair value. In the nine months ended September 30, 2023, we recognized a $4.0 million unrealized loss in our condensed consolidated statements of operations related to a decrease in the fair value of our investments in publicly traded companies.
[3] | Our privately held equity securities are included in deposits and other assets. We recognize our privately held equity securities at cost minus impairments, plus or minus changes resulting from observable price changes in orderly transactions for the identical or similar investment of the same issuer, which are Level 3 inputs. In the nine months ended September 30, 2023, we recorded a net gain of $2.6 million in our condensed consolidated statements of operations related to changes in the fair value of our investments in privately held companies.

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