Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

Debt Instrument, Decrease, Principal Forgiveness Period under the Terms of the Loan

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No definition available.

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- Definition

Debt instrument interest additional interest above base rate.

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- Definition

Debt Instrument, Payment Terms, Period Principal Payments are Deferred

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- Definition

Floating Euro Dollar Based Rate

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ 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(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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

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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.

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No definition available.

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- 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.

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No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: 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

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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Balance Type:	credit
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- Definition

Amount of decrease in line of credit facility from forgiveness by the holder of the line of credit.

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No definition available.

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

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

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

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Debt (Detail) - Borrowings - USD ($)	9 Months Ended	12 Months Ended
Debt (Detail) - Borrowings - USD ($)	Sep. 30, 2015	Dec. 31, 2012	Dec. 31, 2014
Debt Instrument [Line Items]
Long-term line of credit	$ 840,000,000		$ 405,000,000
Debt instrument, interest, additional interest above base rate	1.375%
Notional amount of interest rate derivatives	$ 711,600,000		245,650,000
Line of credit facility, remaining borrowing capacity	645,600,000
Line of credit facility, maximum borrowing capacity	$ 1,500,000,000.0
Debt instrument, effective percentage	2.77%
Minimum
Debt Instrument [Line Items]
Floating eurodollar based rate	0.19%
Maximum
Debt Instrument [Line Items]
Floating eurodollar based rate	0.25%
Term loans
Debt Instrument [Line Items]
Long-term line of credit	$ 385,000,000		400,000,000
Line of credit facility, maximum borrowing capacity	$ 400,000,000
Term loans \| Minimum
Debt Instrument [Line Items]
Contractual annualized interest rate	1.63%
Term loans \| Maximum
Debt Instrument [Line Items]
Contractual annualized interest rate	1.57%
Revolver loans
Debt Instrument [Line Items]
Long-term line of credit	$ 450,000,000		0
Line of credit facility, maximum borrowing capacity	$ 1,100,000,000.0
Revolver loans \| Minimum
Debt Instrument [Line Items]
Contractual annualized interest rate	1.57%
Revolver loans \| Maximum
Debt Instrument [Line Items]
Contractual annualized interest rate	1.63%
Other
Debt Instrument [Line Items]
Long-term line of credit	$ 5,000,000		$ 5,000,000
Connecticut Economic Development Program
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 5,000,000.0
Debt instrument, fixed interest rate		3.00%
Debt instrument term		10 years
Debt instrument, period principal payments are deferred		5 years
Line of credit facility, decrease, forgiveness (up to)		$ 2,500,000.0
Debt instrument, forgiveness period under the terms of the loan		5 years
Interest rate swap
Debt Instrument [Line Items]
Notional amount of interest rate derivatives	$ 700,000,000