Debt (Richmond Credit Facility Narrative) (Details) - Richmond Credit Facility [Member] $ in Millions	9 Months Ended
Sep. 30, 2015 USD ($)
Debt Instrument [Line Items]
Credit facility, maturity date	Jun. 30, 2019
Current revolving credit facility	$ 120
Line of credit facility weighted average interest rate outstanding percentage	2.29%
Maximum [Member]
Debt Instrument [Line Items]
Increased borrowing capacity after considering accordion feature	$ 200
Maximum [Member] \| Libor Rate [Member]
Debt Instrument [Line Items]
Leverage ratio	2.85%
Maximum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Leverage ratio	1.85%
Minimum [Member] \| Libor Rate [Member]
Debt Instrument [Line Items]
Leverage ratio	2.10%
Minimum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Leverage ratio	1.10%

Increased borrowing capacity after considering accordion feature.

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Leverage Ratio Limit Under Existing Revolving Credit Facility

+ References

No definition available.

+ Details

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- Definition

Line Of Credit Facility Weighted Average Percentage Outstanding Interest Rate.

+ References

No definition available.

+ Details

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Period Type:	instant

- 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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Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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- Details

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- Details

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- Details

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