Debt Instrument, Amended Leverage Ratio

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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

- 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

+ Details

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Period Type:	instant

- 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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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- 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)

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

+ Details

Name:	us-gaap_DebtInstrumentPeriodicPaymentPrincipal
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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

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

- 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
Balance Type:	na
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

Name:	us-gaap_LettersOfCreditOutstandingAmount
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))

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

+ Details

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

- 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))

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

+ Details

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

- 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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Data Type:	num:percentItemType
Balance Type:	na
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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- Details

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- Details

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- Details

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- Details

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Long-Term Debt (Credit Agreement) (Details)	1 Months Ended		3 Months Ended				18 Months Ended
Long-Term Debt (Credit Agreement) (Details)	Jan. 31, 2014	Jun. 30, 2013 USD ($)	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2015 USD ($)	Jun. 30, 2015	Dec. 31, 2016	Sep. 30, 2013 USD ($)
Debt Instrument [Line Items]
Amended leverage ratio	3.5					4
Scenario, Forecast [Member]
Debt Instrument [Line Items]
Amended leverage ratio			3.5	4			4.5
Term Loan Maturing June 2018 [Member]
Debt Instrument [Line Items]
Original borrowing capacity		$ 300,000,000
Debt instrument, periodic payment terms, balloon payment to be paid		$ 180,000,000
Debt instrument, maturity date		Jun. 19, 2018
Term Loan Maturing June 2018 [Member] \| Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Derivative, notional amount								$ 148,100,000
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 spread on variable rate					2.50%
Revolving Credit Facility Maturing June 2018 [Member]
Debt Instrument [Line Items]
Original borrowing capacity		$ 600,000,000
Line of credit facility, maximum additional commitments		$ 200,000,000
Revolving credit facility available capacity					$ 243,400,000
Unsecured letters of credit					$ 17,500,000
Commitment fee percentage					0.50%
Minimum [Member] \| Term Loan Maturing June 2018 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate					2.00%
Minimum [Member] \| Term Loan Maturing June 2018 [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate					1.00%
Maximum [Member] \| Term Loan Maturing June 2018 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate					4.00%
Maximum [Member] \| Term Loan Maturing June 2018 [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate					3.00%
Years One and Two \| Term Loan Maturing June 2018 [Member]
Debt Instrument [Line Items]
Debt instrument, periodic payment, principal, percentage		5.00%
Debt instrument, periodic payment, principal		$ 15,000,000
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		$ 30,000,000