Reportable Segments (Capital Expenditures, Depreciation and Total Assets) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Capital Expenditures	$ 12,658us-gaap_PaymentsForCapitalImprovements	$ 11,744us-gaap_PaymentsForCapitalImprovements	$ 15,182us-gaap_PaymentsForCapitalImprovements
Depreciation and Amortization	13,137	11,927	9,516
Total Assets	538,759us-gaap_Assets	509,723us-gaap_Assets
Joining Materials
Segment Reporting Information [Line Items]
Capital Expenditures	5,128	3,135	2,951
Depreciation and Amortization	3,204	2,682	1,110
Total Assets	107,387	108,621
Tubing
Segment Reporting Information [Line Items]
Capital Expenditures	2,835	3,679	5,157
Depreciation and Amortization	2,401	2,399	2,250
Total Assets	36,160	37,550
Building Materials
Segment Reporting Information [Line Items]
Capital Expenditures	2,661	3,424	4,776
Depreciation and Amortization	5,217	4,600	4,132
Total Assets	137,270	134,320
Kasco
Segment Reporting Information [Line Items]
Capital Expenditures	1,989	1,339	2,236
Depreciation and Amortization	2,162	2,095	1,920
Total Assets	22,599	23,612
Corporate and other
Segment Reporting Information [Line Items]
Capital Expenditures	45	167	62
Depreciation and Amortization	153	151	104
Total Assets	165,670	137,476
Discontinued operations
Segment Reporting Information [Line Items]
Total Assets	69,673	68,144
Inactive Properties
Segment Reporting Information [Line Items]
Total Assets	$ 8,400	$ 9,100

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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 210.5-02.18)

-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 210

-SubTopic 10

-Section S99

-Paragraph 1

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 7

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 18

-Article 5

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

The cash outflow for acquisition of or capital improvements to properties held for investment (operating, managed, leased) or for use.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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