Segments and Related Information (Schedule of Financial Information by Reportable Segment - EBITDA - Continuing Operations) (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Jun. 30, 2014	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
EBITDA - Continuing Operations:
EBITDA - Continuing operations	$ 134.2	$ 104.2	$ 65.3	$ 169.5	$ 303.6	$ 403.7	$ 427.6	$ 322.1
Electrical Transmission [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations	$ 19.0	$ 19.0	$ (3.0)	$ 17.0	$ 35.0
Reportable Segments [Member] | Communications [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations						204.0	247.7	192.0
Reportable Segments [Member] | Oil and Gas [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations						195.1	215.9	99.4
Reportable Segments [Member] | Electrical Transmission [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations						45.0	41.2	38.7
Reportable Segments [Member] | Power Generation and Industrial [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations						14.2	(16.3)	32.0
Reportable Segments [Member] | Other [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations						(1.2)	0.5	2.0
Corporate [Member]
EBITDA - Continuing Operations:
EBITDA - Continuing operations						$ (53.4)	$ (61.4)	$ (42.0)