Investments (Schedule of Variable Interest Entities) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
LB Pipe & Coupling Products, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Maximum exposure to loss	$ 5,780	$ 6,008
LB Pipe JV equity method investment [Member] | LB Pipe & Coupling Products, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Maximum exposure to loss	3,704	3,902
Revolving line of credit [Member] | LB Pipe & Coupling Products, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Maximum exposure to loss	1,235	1,235
Net investment in direct financing lease [Member]
Schedule of Equity Method Investments [Line Items]
Maximum exposure to loss	$ 841	$ 871