Amount of the required periodic payments applied to principal as a percentage.

No definition available.

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- Definition

The maximum additional commitments that may be requested under the credit facility.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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

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

+ References

No definition available.

+ Details

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- Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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)(2))

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

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- Definition

Amount of the required periodic payments applied to principal.

+ 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)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

High end of the range of percentage points added to the reference rate to compute the variable rate on the group of interest rate derivatives.

+ References

No definition available.

+ Details

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- Definition

Low end of the range of percentage points added to the reference rate to compute the variable rate on the group of interest rate derivatives.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	instant

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

- 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.

+ 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 210.5-02.19(b),22(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

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

+ 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 210.5-02.19(b),22(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Balance Type:	credit
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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.

+ Details

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- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with either short term or long term maturity that is uncollateralized (where debt is not backed by the pledge of collateral).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Details

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Long-Term Debt (Credit Agreement) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended	1 Months Ended	3 Months Ended
	Dec. 31, 2014	Jul. 31, 2013	Mar. 31, 2012	Sep. 30, 2013	Jun. 30, 2013
Debt Instrument [Line Items]
Debt intstrument, maturity date	Jun. 19, 2018
Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Notional amount of derivative				$ 148.1
Term Loan Maturing June 2018 [Member]
Debt Instrument [Line Items]
Original borrowing capacity					300
Proceeds from unsecured lines of credit		300
Debt instrument, periodic payment terms, balloon payment to be paid	180.0
Term Loan Maturing June 2018 [Member] \| Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Derivative, lower range of basis spread on variable rate				0.74%
Derivative, higher range of basis spread on variable rate				0.75%
Term Loan Maturing June 2018 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis point spread	2.25%
Revolving Credit Facility Maturing June 2018 [Member]
Debt Instrument [Line Items]
Original borrowing capacity					600
Line of credit facility, maximum additional commitments	200
Revolving credit facility available	583.6
Unsecured letters of credit	16.4
Commitment fee percentage	0.375%
Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Repayments of debt		275.0	200.0
Minimum [Member] \| Term Loan Maturing June 2018 [Member]
Debt Instrument [Line Items]
Basis point spread	1.00%
Minimum [Member] \| Loans [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis point spread	2.00%
Maximum [Member] \| Term Loan Maturing June 2018 [Member]
Debt Instrument [Line Items]
Basis point spread	2.00%
Maximum [Member] \| Loans [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis point spread	3.00%
Years One And Two [Member] \| Term Loan Maturing June 2018 [Member]
Debt Instrument [Line Items]
Debt instrument, periodic payment, principal, percentage	5.00%
Debt instrument, periodic payment, principal	15.0
Years Three Through Five [Member] \| Term Loan Maturing June 2018 [Member]
Debt Instrument [Line Items]
Debt instrument, periodic payment, principal, percentage	10.00%
Debt instrument, periodic payment, principal	30.0