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Debt - Borrowings (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Debt Instrument [Line Items] |  |
Principal amount outstanding | $ 2,494,461 | $ 2,006,046
Less: deferred financing fees | (31,492) | (27,245)
Net balance sheet carrying amount | 2,462,969 | 1,978,801
Term Loan Facility | 2020 Credit Agreement |  |
Debt Instrument [Line Items] |  |
Principal amount outstanding | 288,800 | 395,000
Line of Credit | Revolving credit facility | 2020 Credit Agreement |  |
Debt Instrument [Line Items] |  |
Principal amount outstanding | 0 | 5,000
Senior Notes | 2028 Notes |  |
Debt Instrument [Line Items] |  |
Principal amount outstanding | 800,000 | 800,000
Senior Notes | 2029 Notes |  |
Debt Instrument [Line Items] |  |
Principal amount outstanding | 600,000 | 0
Senior Notes | 2030 Notes |  |
Debt Instrument [Line Items] |  |
Principal amount outstanding | 800,000 | 800,000
Other |  |
Debt Instrument [Line Items] |  |
Principal amount outstanding | 5,661 | $ 6,046
Connecticut Economic Development Program | Economic Development Loan 1 |  |
Debt Instrument [Line Items] |  |
Principal amount outstanding | $ 700 |

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