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Goodwill - Narrative (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jan. 09, 2024 | Mar. 31, 2024 | Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023 | Dec. 31, 2022
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |  |  |
Payments to acquire businesses, gross |  | $ 7,831 |  | $ 0 |  |
Goodwill |  | 9,018,301 | $ 9,018,301 |  | $ 9,022,075 | $ 8,971,670
Amortization of intangible assets |  | 116,500 |  |  | 459,900 |
Goodwill, impairment loss |  | 0 |  |  | $ 0 |
HumanFirst Inc |  |  |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |  |  |
Business combination, consideration transferred | $ 13,300 |  |  |  |  |
Payments to acquire businesses, gross | 11,800 |  |  |  |  |
Payments to acquire businesses, net of cash acquired | 7,800 |  |  |  |  |
Cash acquired from acquisition | 4,000 |  |  |  |  |
Deferred consideration |  | $ 1,500 | 1,500 |  |  |
Goodwill | 2,700 |  |  |  |  |
Intangible assets acquired | $ 9,900 |  |  |  |  |
Finite-lived intangible asset, useful life | 5 years |  |  |  |  |
Amortization of intangible assets |  |  | $ 500 |  |  |

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