Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Schedule of AOCI) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Increase (Decrease) in Accumulated Other Comprehensive Income [Rollforward]
Balance at beginning of period	$ (7,524)	$ (13,948)
Other comprehensive income before reclassifications	(6,689)	5,288
Amounts reclassified from accumulated other comprehensive loss, net of tax of $(1.2) million	2,357	1,136
Net current period other comprehensive income, net	(4,332)	6,424
Accumulated other comprehensive (loss) income	(11,856)	(7,524)
Income tax benefit	(1,209)	(617)
Pension and postretirement benefits
Increase (Decrease) in Accumulated Other Comprehensive Income [Rollforward]
Balance at beginning of period	(9,280)	(15,532)
Other comprehensive income before reclassifications	(4,968)	5,116
Amounts reclassified from accumulated other comprehensive loss, net of tax of $(1.2) million	2,357	1,136
Net current period other comprehensive income, net	(2,611)	6,252
Accumulated other comprehensive (loss) income	(11,891)	(9,280)
Income tax benefit	(1,209)	(617)
Foreign currency
Increase (Decrease) in Accumulated Other Comprehensive Income [Rollforward]
Balance at beginning of period	1,756	1,584
Other comprehensive income before reclassifications	(1,721)	172
Amounts reclassified from accumulated other comprehensive loss, net of tax of $(1.2) million	0	0
Net current period other comprehensive income, net	(1,721)	172
Accumulated other comprehensive (loss) income	35	1,756
Income tax benefit	$ 0	$ 0

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Reclassification From Accumulated Other Comprehensive Income, Current Period, Tax

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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e681-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14A

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 31

-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

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-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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-Name Accounting Standards Codification

-Topic 220

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-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669619-108580

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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