Debt Instrument, Additional Interest above Base Rate

No definition available.

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- Definition

Debt Instrument, Payment Terms, Period Principal Payments are Deferred

+ References

No definition available.

+ Details

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- Definition

Debt, Long-term and Short-term, Combined Amount, Gross

+ References

No definition available.

+ Details

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- Definition

Floating Euro Dollar Base Rate

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- 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

No definition available.

+ Details

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Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Period Type:	duration

- 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section S45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68176171&loc=SL68176184-208336

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

+ Details

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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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Debt - Borrowings (Details) - USD ($)		3 Months Ended		12 Months Ended
Debt - Borrowings (Details) - USD ($)	Apr. 30, 2018	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2012	Dec. 31, 2017
Debt Instrument [Line Items]
Principal amount outstanding		$ 3,018,135,000			$ 3,323,062,000
Less: deferred financing fees		(42,350,000)			(44,217,000)
Net balance sheet carrying amount		$ 2,975,785,000			3,278,845,000
Average annual effective rate		4.14%
Repayments of debt		$ 304,813,000	$ 0
Subsequent Event
Debt Instrument [Line Items]
Repayments of debt	$ 450,000,000
Revolving credit facility
Debt Instrument [Line Items]
Long-term debt, gross		$ 310,000,000			595,000,000
Contractual annualized interest rate		4.38%
Floating eurodollar base rate		1.88%
Debt instrument interest additional interest above base rate		2.50%
Line of credit facility, remaining borrowing capacity		$ 866,000,000
Revolving credit facility \| Subsequent Event
Debt Instrument [Line Items]
Repayments of debt	50,000,000
Bank Term Loan - A Facility
Debt Instrument [Line Items]
Long-term debt, gross		$ 1,410,750,000			1,429,312,000
Contractual annualized interest rate		3.88%
Floating eurodollar base rate		1.88%
Debt instrument interest additional interest above base rate		2.00%
Bank Term Loan - B Facility
Debt Instrument [Line Items]
Long-term debt, gross		$ 495,000,000			496,250,000
Contractual annualized interest rate		3.23%
Floating eurodollar base rate		1.23%
Debt instrument interest additional interest above base rate		2.00%
Bank Term Loan - B Facility \| Subsequent Event
Debt Instrument [Line Items]
Repayments of debt	$ 400,000,000
Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross		$ 800,000,000			800,000,000
Debt instrument, fixed interest rate		5.125%
Connecticut Economic Development Program
Debt Instrument [Line Items]
Long-term debt, gross		$ 2,385,000		$ 2,500,000.0	$ 2,500,000
Debt instrument term				10 years
Debt instrument, fixed interest rate				3.00%
Debt instrument, period principal payments are deferred				5 years