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v3.25.1

Investments, Summary of Investments (Details) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2025 USD ($) Company | Dec. 31, 2024 USD ($)
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 |  | $ 1,233,261 | $ 1,402,258
Gross unrealized gains |  | 850 | 1,607
Gross unrealized losses |  | (549) | (399)
Estimated fair value |  | 1,233,562 | 1,403,466
Available-for-sale Debt Securities with Maturity of More Than One Year [Abstract] |  |  |
Amortized cost |  | 680,878 | 654,600
Gross unrealized gains |  | 1,648 | 984
Gross unrealized losses |  | (1,177) | (3,042)
Estimated fair value |  | 681,349 | 652,542
Available-for-sale Debt Securities [Abstract] |  |  |
Amortized cost |  | 1,914,139 | 2,056,858
Gross unrealized gains |  | 2,498 | 2,591
Gross unrealized losses |  | (1,726) | (3,441)
Estimated fair value |  | 1,914,911 | 2,056,008
Equity Securities [Abstract] |  |  |
Amortized cost |  | 35,012 | 35,012
Gross unrealized gains |  | 25,042 | 25,027
Gross unrealized losses |  | (15,949) | (13,753)
Estimated fair value |  | 44,105 | 46,286
Available-for-sale Debt and Equity Securities [Abstract] |  |  |
Amortized cost |  | 1,949,151 | 2,091,870
Gross unrealized gains |  | 27,540 | 27,618
Gross unrealized losses |  | (17,675) | (17,194)
Estimated fair value |  | 1,959,016 | 2,102,294
Corporate Debt Securities [Member] |  |  |
Available-for-sale Debt Securities with Maturity of One Year or Less [Abstract] |  |  |
Amortized cost | [1] | 516,458 | 593,810
Gross unrealized gains |  | 299 | 487
Gross unrealized losses |  | (247) | (240)
Estimated fair value |  | 516,510 | 594,057
Available-for-sale Debt Securities with Maturity of More Than One Year [Abstract] |  |  |
Amortized cost |  | 471,479 | 439,561
Gross unrealized gains |  | 1,086 | 723
Gross unrealized losses |  | (1,009) | (2,275)
Estimated fair value |  | 471,556 | 438,009
Debt Securities Issued by U.S. Government Agencies [Member] |  |  |
Available-for-sale Debt Securities with Maturity of One Year or Less [Abstract] |  |  |
Amortized cost |  | 120,961 | 143,647
Gross unrealized gains |  | 156 | 287
Gross unrealized losses |  | (32) | (39)
Estimated fair value |  | 121,085 | 143,895
Available-for-sale Debt Securities with Maturity of More Than One Year [Abstract] |  |  |
Amortized cost |  | 61,184 | 65,255
Gross unrealized gains |  | 188 | 137
Gross unrealized losses |  | (116) | (289)
Estimated fair value |  | 61,256 | 65,103
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] | 592,770 | 657,285
Gross unrealized gains |  | 393 | 825
Gross unrealized losses |  | (270) | (120)
Estimated fair value |  | 592,893 | 657,990
Available-for-sale Debt Securities with Maturity of More Than One Year [Abstract] |  |  |
Amortized cost |  | 145,922 | 149,086
Gross unrealized gains |  | 373 | 124
Gross unrealized losses |  | (52) | (476)
Estimated fair value |  | 146,243 | 148,734
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 |  | 3,072 | 7,516
Gross unrealized gains |  | 2 | 8
Gross unrealized losses |  | 0 | 0
Estimated fair value |  | 3,074 | 7,524
Available-for-sale Debt Securities with Maturity of More Than One Year [Abstract] |  |  |
Amortized cost |  | 1,595 |
Gross unrealized gains |  | 1 |
Gross unrealized losses |  | 0 |
Estimated fair value |  | 1,596 |
Other Municipal Debt Securities [Member] |  |  |
Available-for-sale Debt Securities with Maturity of More Than One Year [Abstract] |  |  |
Amortized cost |  | 698 | 698
Gross unrealized gains |  | 0 | 0
Gross unrealized losses |  | 0 | (2)
Estimated fair value |  | 698 | 696
Publicly Traded Equity Securities [Member] |  |  |
Equity Securities [Abstract] |  |  |
Amortized cost | [2] | 11,897 | 11,897
Gross unrealized gains |  | 41 | 26
Gross unrealized losses |  | (8,856) | (6,660)
Estimated fair value |  | 3,082 | 5,263
Available-for-sale Debt and Equity Securities [Abstract] |  |  |
Unrealized loss on equity securities |  | (2,200) |
Privately Held Equity Securities [Member] |  |  |
Equity Securities [Abstract] |  |  |
Amortized cost | [3] | 23,115 | 23,115
Gross unrealized gains |  | 25,001 | 25,001
Gross unrealized losses |  | (7,093) | (7,093)
Estimated fair value |  | $ 41,023 | $ 41,023
[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 three months ended March 31, 2025, we recorded a $2.2 million net unrealized loss in our condensed consolidated statements of operations related to changes 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.

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