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

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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