Represents the number of tranches comprising the debt issuance.

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Represents the lump sum amount payable at the maturity of the debt instrument.

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No definition available.

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Represents the percentage of annual amortization of term loan after specified period.

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No definition available.

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Represents the redemption price as a percentage of the principal amount at which the debt instrument may be required to be redeemed by the entity in the event of a change of control or downgrade of the entity's credit rating.

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No definition available.

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- Definition

The contingent increase above the maximum borrowing capacity under the credit facility, if any one or more of the existing banks or new banks agree to provide such increased commitment amount.

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No definition available.

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The number of financial covenants.

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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.

+ References

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.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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Debt - Other (Details) $ in Millions			1 Months Ended	6 Months Ended
Debt - Other (Details) $ in Millions	Apr. 12, 2013 USD ($)	Nov. 20, 2006 USD ($) tranche	Sep. 30, 2016 USD ($)	Jun. 30, 2019 USD ($) item	Dec. 31, 2018 USD ($)	Nov. 15, 2016 USD ($)
Debt
Total				$ 2,019.3	$ 2,214.2
Number of financial covenants \| item				2
Credit Agreement
Debt
Maximum borrowing capacity			$ 2,100.0
Debt term			5 years
Unsecured revolving credit facility due September 30, 2021
Debt
Maximum borrowing capacity			$ 1,500.0
Total				$ 760.0	$ 925.0
Additional maximum borrowing capacity under the credit agreement subject to approval of the lenders and certain other conditions			500.0
Commitment fee on unused portion of revolving credit facility (as a percent)				0.15%
Weighted average fixed interest rate (as a percent)				3.79%	3.86%
Letters of credit outstanding				$ 41.0
Available on the revolving credit facility				$ 699.0
Unsecured revolving credit facility due September 30, 2021 \| LIBOR
Debt
Variable interest rate				LIBOR
Interest rate added to base (as a percent)				1.25%
Unsecured revolving credit facility due September 30, 2021 \| Bank prime rate
Debt
Variable interest rate				bank prime
Interest rate added to base (as a percent)				0.25%
Unsecured term loan due from September 30, 2019 to September 30, 2021
Debt
Total				$ 495.0	$ 525.0
Debt amount			$ 600.0
Annual amortization of term loan thereafter until June 2021 (as a percent)			10.00%
Weighted average fixed interest rate (as a percent)				3.65%	3.77%
Unsecured term loan due from September 30, 2019 to September 30, 2021 \| LIBOR
Debt
Variable interest rate				LIBOR
Interest rate added to base (as a percent)				1.25%
Unsecured term loan due from September 30, 2019 to September 30, 2021 \| Bank prime rate
Debt
Variable interest rate				bank prime
Interest rate added to base (as a percent)				0.25%
Senior Unsecured Notes
Debt
Percentage of principal amount at which the notes may be required to be repurchased in event of a change of control and a downgrade of the entity's credit rating				101.00%
Senior unsecured notes issued November 20, 2006
Debt
Issuance of debt		$ 600.0
Number of tranches comprising the debt issuance \| tranche		2
Senior unsecured notes due November 15, 2016
Debt
Total						$ 0.0
Interest rate (as a percent)		6.20%
Lump sum payment on maturity						$ 350.0
Issuance of debt		$ 350.0
Senior unsecured notes due April 15, 2023
Debt
Total				$ 500.0	$ 500.0
Interest rate (as a percent)	4.50%
Issuance of debt	$ 500.0
Senior unsecured notes due November 15, 2036
Debt
Total				250.0	250.0
Interest rate (as a percent)		6.85%
Issuance of debt		$ 250.0
Other notes and revolving credit facilities
Debt
Maximum borrowing capacity				10.0
Total				4.8	4.7
IRB
Debt
Total				$ 9.5	$ 9.5