Debt - Borrowings (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,312,092	$ 3,323,062
Less: deferred financing fees	(30,405)	(44,217)
Net balance sheet carrying amount	2,281,687	3,278,845
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	155,000	595,000
Term loan
Debt Instrument [Line Items]
Long-term debt, gross	1,355,062	1,429,312
Term B facility
Debt Instrument [Line Items]
Long-term debt, gross	0	496,250
Senior notes
Debt Instrument [Line Items]
Long-term debt, gross	800,000	800,000
Connecticut Economic Development Program
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,030	$ 2,500

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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