Debt - Borrowings (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,207,514	$ 2,312,092
Less: deferred financing fees	(23,908)	(30,405)
Net balance sheet carrying amount	2,183,606	2,281,687
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	148,000	155,000
Term loan
Debt Instrument [Line Items]
Long-term debt, gross	1,252,969	1,355,062
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	$ 6,545	$ 2,030

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
-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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- Definition

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

+ References

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