Goodwill and Other Intangibles (Changes in the Net Carrying Amount of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Goodwill [Roll Forward]
Balance at beginning of period	$ 68,214us-gaap_Goodwill	$ 50,485us-gaap_Goodwill
Foreign Currency Translation Adjustments	(37)us-gaap_GoodwillTranslationAdjustments	14us-gaap_GoodwillTranslationAdjustments
Additions	0	18,169
Adjustments	76us-gaap_GoodwillOtherChanges	(454)us-gaap_GoodwillOtherChanges
Balance at end of period	68,253us-gaap_Goodwill	68,214us-gaap_Goodwill
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Accumulated Impairment Losses	0
Joining Materials
Goodwill [Roll Forward]
Balance at beginning of period	16,275	1,494
Foreign Currency Translation Adjustments	(37)	14
Additions	0
Adjustments	0	0
Balance at end of period	16,238	16,275
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Accumulated Impairment Losses	0	0
Tubing
Goodwill [Roll Forward]
Balance at beginning of period	1,895	1,895
Foreign Currency Translation Adjustments	0	0
Additions	0	0
Adjustments	0	0
Balance at end of period	1,895	1,895
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Accumulated Impairment Losses	0	0
Building Materials
Goodwill [Roll Forward]
Balance at beginning of period	50,044	47,096
Foreign Currency Translation Adjustments	0	0
Additions	0
Adjustments	76
Balance at end of period	50,120	50,044
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Accumulated Impairment Losses	$ 0	$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of other (increase) decrease of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

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-Section 25

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-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e961-128460

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Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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