Reportable Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Net sales	$ 137,982us-gaap_SalesRevenueGoodsNet	$ 135,487us-gaap_SalesRevenueGoodsNet
Segment operating income:	5,446us-gaap_OperatingIncomeLoss	5,353us-gaap_OperatingIncomeLoss
Unallocated pension expense	(2,072)us-gaap_PensionExpense	(1,105)us-gaap_PensionExpense
Interest expense	(1,167)us-gaap_InterestExpenseDebt	(1,546)us-gaap_InterestExpenseDebt
Realized and unrealized (loss) gain on derivatives	(207)	140
Other expense	(93)us-gaap_NonoperatingIncomeExpense	(69)us-gaap_NonoperatingIncomeExpense
Income from continuing operations before tax and equity investment	3,979	3,878
Joining Materials
Segment Reporting Information [Line Items]
Net sales	47,793	51,713
Segment operating income:	6,247	5,378
Tubing
Segment Reporting Information [Line Items]
Net sales	21,080	20,706
Segment operating income:	3,080	3,068
Building Materials
Segment Reporting Information [Line Items]
Net sales	54,989	48,531
Segment operating income:	3,233	3,010
Kasco
Segment Reporting Information [Line Items]
Net sales	14,120	14,537
Segment operating income:	863	726
Total segment operating income
Segment Reporting Information [Line Items]
Segment operating income:	13,423	12,182
Reconciling Items
Segment Reporting Information [Line Items]
Segment operating income:	(5,960)	(5,747)
Unallocated pension expense	(2,072)	(1,105)
Gain from asset dispositions	$ 55	$ 23

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

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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

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The amount of pension benefit costs recognized during the period for (1) defined benefit plans and (2) defined contribution plans. For defined benefit plans, pension expense includes the following components: service cost, interest cost, expected return on plan assets, gain (loss) on plan assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. For defined contribution plans, the pension expense generally equals the firm's contribution to employees' accounts (if the firm contributes) during the period.

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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