Debt (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Senior Notes	$ 250.0
Unused capacity, commitment fee percentage	0.25%
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 450.0
Maximum letters of credit issuance	$ 75.0
Minimum fixed charge coverage ratio	1.00
Threshold for excess availability	$ 40.0
Debt Instrument, Covenant Compliance, Threshold For Line Cap Percentage	10.00%
Debt Instrument, Covenant Compliance, Minimum Excess Availability For 30 Consecutive Days	$ 40.0
Debt Instrument, Covenant Compliance, Minimum Line Cap Percentage For 30 Consecutive Days	10.00%
Revolving line of credit	$ 152.3
Remaining borrowing capacity	127.3
Letters of credit, amount outstanding	$ 64.6
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Outstanding letters of credit fee	0.75%
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Outstanding letters of credit fee	1.25%
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| Base Rate Option [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.25%
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| Base Rate Option [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.75%
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| LIBOR Rate Option [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| LIBOR Rate Option [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| LIBOR Rate Option [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| Federal Funds Rate [Member] \| Base Rate Option [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Revolving line of credit	$ 129.0
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Interest rate at period end	1.70%
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Interest rate at period end	1.90%
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| FILO [Member]
Debt Instrument [Line Items]
Revolving line of credit	$ 21.0
Interest rate at period end	2.70%
Revolving Credit Facility [Member] \| Wells Fargo Capital Finance [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Revolving line of credit	$ 2.3
Interest rate at period end	4.00%
Secured By Equipment [Member]
Debt Instrument [Line Items]
Other long-term debt	$ 5.8
Secured By Property [Member]
Debt Instrument [Line Items]
Other long-term debt	$ 0.5
Senior Notes [Member]
Debt Instrument [Line Items]
Maturity date	Sep. 15, 2018
Interest rate	9.00%
Redemption price percentage	106.75%
Redemption price percentage in following year	103.375%
Market value in excess of carrying value	$ 10.6
Other [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Interest rate	4.60%
Other [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Interest rate	8.40%
Other [Member] \| Secured By Equipment [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date Range, End	Apr. 30, 2019
Other [Member] \| Secured By Property [Member]
Debt Instrument [Line Items]
Maturity date	Mar. 31, 2021

Minimum excess availability needed for 30 consecutive days to be in compliance with covenant.

No definition available.

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- Definition

Debt Instrument, Covenant Compliance, Minimum Fixed Charge Coverage Ratio

+ References

No definition available.

+ Details

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- Definition

Minimum line cap percentage needed for 30 consecutive days to be in compliance with covenant.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of excess availability to be in compliance with covenant.

+ References

No definition available.

+ Details

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- Definition

Minimum percent of line cap to be in compliance with covenant.

+ References

No definition available.

+ Details

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer in following year.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The fee charged for any outstanding letters of credit issued under the revolving line of credit.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum amount of revolving line of credit that can be used for issuance of letters of credit.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Amount of fair value of long-term debt in excess of carrying amount.

+ References

No definition available.

+ 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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- Definition

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

+ References

+ Details

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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.

+ Details

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- Definition

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

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

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

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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

+ 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

+ Details

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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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Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the 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)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=28361426&loc=d3e1314-112600

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=28361426&loc=d3e1336-112600

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Line-of-Credit Arrangement
-URI http://asc.fasb.org/extlink&oid=6517033

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16(a))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	instant

- Details

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