Segments and Related Information (Schedule of Financial Information by Reportable Segment - EBITDA - Continuing Operations) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
EBITDA - Continuing Operations:
EBITDA - Continuing operations	$ 53.8	$ 104.2	$ 96.6	$ 169.5
Reportable Segments [Member] | Communications [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations	40.5	57.8	92.2	101.3
Reportable Segments [Member] | Oil and Gas [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations	41.3	36.3	62.9	70.9
Reportable Segments [Member] | Electrical Transmission [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations	(21.4)	19.3	(23.9)	16.6
Reportable Segments [Member] | Power Generation and Industrial [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations	8.0	3.9	(0.9)	4.5
Reportable Segments [Member] | Other [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations	0.0	0.3	(5.1)	0.6
Corporate [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations	$ (14.6)	$ (13.4)	$ (28.6)	$ (24.4)