Segments and Related Information (Schedule of Significant Customers, Revenue Concentration Information) (Details) - Customer Concentration Risk [Member] - Revenue [Member]		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
AT&T (including DIRECTV) [Member] | Communications [Member]
Revenue, Significant Customer [Line Items]
Significant customers, percentage of total consolidated revenue	[1],[2]	32.00%	33.00%	32.00%
Enbridge, Inc. [Member] | Oil and Gas [Member]
Revenue, Significant Customer [Line Items]
Significant customers, percentage of total consolidated revenue	[3]	1.00%	8.00%	18.00%

[1] DIRECTV® was acquired by AT&T in July 2015. Revenue from DIRECTV® is presented on a combined basis with AT&T for all periods.

[2] The Company’s relationship with AT&T is based upon multiple separate master service agreements, other service agreements and construction/installation contracts for AT&T’s (i) wireless, (ii) wireline/fiber, (iii) home security and automation businesses, and (iv) for DIRECTV® services, is based upon an agreement to provide installation and maintenance services. Revenue from AT&T is included in the Communications segment.

[3] The Company's relationship with Enbridge, Inc. is based upon various construction contracts for pipeline activities. Revenue from Enbridge, Inc. is primarily included in the Oil and Gas segment.