Length of a capital lease renewal period.

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Balloon payment related to a capital lease that is required to be paid either at the termination of the lease or during the initial term of the lease.

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Amount of current monthly capital lease payments.

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Maximum lending capacity under the credit facility without consideration of any current restrictions on the amount that could be lended or the amounts currently outstanding under the facility.

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Area of land held.

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- Definition

Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

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The number of units (items of property) under capital lease arrangements.

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No definition available.

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Amounts due from an entity in which the reporting entity shares joint control with another party or group, due within 1 year (or 1 business cycle).

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Investments (Narrative) (Details) $ in Thousands	3 Months Ended		12 Months Ended
Investments (Narrative) (Details) $ in Thousands	Mar. 31, 2018 USD ($) a facility	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Schedule of Equity Method Investments
Equity investments	$ 159		$ 162
Assets held for sale		$ 3,875
Equity in income (loss) of nonconsolidated investments	$ (3)	(200)
Reclassified
Schedule of Equity Method Investments
Equity investments				$ (4,288)
LB Pipe & Coupling Products, LLC
Schedule of Equity Method Investments
Equity method investment, ownership percentage	45.00%
Other than temporary impairment of equity method investment			413
Equity in income (loss) of nonconsolidated investments	$ 0	$ (198)
Line of credit, maximum lending capacity					$ 1,350
Due from joint ventures, current					$ 1,235
LB Pipe & Coupling Products, LLC \| Capital Leased Land
Schedule of Equity Method Investments
Area of land (in acres) \| a	5
Capital leased assets, number of units \| facility	2
Capital lease length of renewal term	5 years 6 months
Capital Leases, monthly rent	$ 17
Capital leases balloon payment in direct financing leases	$ 488
LB Pipe & Coupling Products, LLC \| Other Joint Venture Member
Schedule of Equity Method Investments
Equity method investment, ownership percentage					45.00%
LB Pipe & Coupling Products, LLC \| Third Party
Schedule of Equity Method Investments
Equity method investment, ownership percentage	45.00%
Other equity investments
Schedule of Equity Method Investments
Equity investments	$ 159		$ 162