The effect of liquidating LIFO (last in first out) inventory layers on income.

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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For the asset that is reclassified back to held and used from held-for-sale, the amount of impairment charge that is recognized on the reclassification date.

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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Reportable Segments (Details) (USD $)	3 Months Ended								12 Months Ended
Reportable Segments (Details) (USD $)	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Net sales:	$ 131,912,000us-gaap_SalesRevenueGoodsNet	$ 164,524,000us-gaap_SalesRevenueGoodsNet	$ 168,545,000us-gaap_SalesRevenueGoodsNet	$ 135,487,000us-gaap_SalesRevenueGoodsNet	$ 129,385,000us-gaap_SalesRevenueGoodsNet	$ 153,151,000us-gaap_SalesRevenueGoodsNet	$ 160,975,000us-gaap_SalesRevenueGoodsNet	$ 127,653,000us-gaap_SalesRevenueGoodsNet	$ 600,468,000us-gaap_SalesRevenueGoodsNet	$ 571,164,000us-gaap_SalesRevenueGoodsNet	$ 498,713,000us-gaap_SalesRevenueGoodsNet
Segment operating income:	4,142,000us-gaap_OperatingIncomeLoss	18,640,000us-gaap_OperatingIncomeLoss	17,585,000us-gaap_OperatingIncomeLoss	5,353,000us-gaap_OperatingIncomeLoss	2,370,000us-gaap_OperatingIncomeLoss	14,563,000us-gaap_OperatingIncomeLoss	15,127,000us-gaap_OperatingIncomeLoss	8,143,000us-gaap_OperatingIncomeLoss	45,720,000us-gaap_OperatingIncomeLoss	40,203,000us-gaap_OperatingIncomeLoss	38,401,000us-gaap_OperatingIncomeLoss
Interest expense									(7,544,000)us-gaap_InterestExpenseDebt	(13,662,000)us-gaap_InterestExpenseDebt	(16,688,000)us-gaap_InterestExpenseDebt
Realized and unrealized gain on derivatives									1,307,000	1,195,000	2,582,000
Other expense									(181,000)us-gaap_NonoperatingIncomeExpense	(240,000)us-gaap_NonoperatingIncomeExpense	(434,000)us-gaap_NonoperatingIncomeExpense
Income from continuing operations before tax and equity investment	2,610,000	17,515,000	15,299,000	3,878,000	1,135,000	12,318,000	14,870,000	(827,000)	39,302,000	27,496,000	23,861,000
Segment Reporting Information, Additional Information [Abstract]
Asset impairment charges									1,179,000	0	0
Operating Segments [Member]
Segment Reporting Information [Line Items]
Segment operating income:									66,161,000	66,343,000	64,803,000
Joining Materials
Segment Reporting Information [Line Items]
Net sales:									207,320,000	195,187,000	174,621,000
Segment operating income:									19,428,000	16,624,000	23,942,000
Segment Reporting Information, Additional Information [Abstract]
Asset impairment charges	600,000
Gains resulting from liquidation of precious metal inventory valued at LIFO cost									600,000	600,000	600,000
Tubing
Segment Reporting Information [Line Items]
Net sales:									81,264,000	91,002,000	80,849,000
Segment operating income:									13,340,000	17,434,000	14,258,000
Building Materials
Segment Reporting Information [Line Items]
Net sales:									253,644,000	226,806,000	189,106,000
Segment operating income:									30,217,000	27,789,000	22,172,000
Kasco
Segment Reporting Information [Line Items]
Net sales:									58,240,000	58,169,000	54,137,000
Segment operating income:									3,176,000	4,496,000	4,431,000
Segment Reporting Information, Additional Information [Abstract]
Asset impairment charge	600,000
Unallocated corporate expenses and non-operating units
Segment Reporting Information [Line Items]
Segment operating income:									(16,878,000)	(21,009,000)	(23,301,000)
Unallocated pension expense
Segment Reporting Information [Line Items]
Segment operating income:									(3,739,000)	(5,206,000)	(3,194,000)
Gain from asset dispositions
Segment Reporting Information [Line Items]
Segment operating income:									$ 176,000	$ 75,000	$ 93,000