Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: 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

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- Definition

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

+ 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))
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- Definition

Amount of the hedged item as of the balance sheet date related to the derivative. For example, the hedged balance on a debt instrument.

+ References

No definition available.

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- Definition

Cap rate on an interest rate derivative such as an interest rate cap or collar. If market rates exceed the cap rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

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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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Derivative Financial Instruments - CF Hedges (Details)	Sep. 30, 2016 USD ($) DerivativeInstrument	Dec. 31, 2015 USD ($)	Jun. 19, 2014 USD ($)	Sep. 30, 2013 USD ($)	Apr. 30, 2011 USD ($)	Oct. 31, 2009 USD ($)
Fair values of derivative financial instruments
Stated interest rate (as a percent)	6.25%
Senior Notes 6.25 Percent Due 2022
Fair values of derivative financial instruments
Aggregate principal amount	$ 375,000,000	$ 375,000,000	$ 375,000,000
Stated interest rate (as a percent)	6.25%		6.25%
Cash Flow Hedges
Fair values of derivative financial instruments
Hedged borrowings	$ 100,000,000
Cash Flow Hedges \| Working Capital Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Fair values of derivative financial instruments
Hedged borrowings	$ 300,000,000
Cash Flow Hedges \| Interest Rate Swaps
Fair values of derivative financial instruments
Number of agreements in place \| DerivativeInstrument	1
Cash Flow Hedges \| Interest Rate Swaps \| Credit Agreement Maturing 2018 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Fair values of derivative financial instruments
Hedged borrowings				$ 100,000,000		$ 100,000,000
Fixed rate (as a percent)				1.819%		3.93%
Cash Flow Hedges \| Interest Rate Cap \| Credit Agreement Maturing 2018 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Fair values of derivative financial instruments
Hedged borrowings					$ 100,000,000
Maximum cap rate (as a percent)					5.50%