Segment and Geographic Information - Assets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Revenues from External Customers and Long-Lived Assets
Assets	$ 2,481.4	$ 1,897.7
Continuing Operations | Operating Segments | D&S East
Revenues from External Customers and Long-Lived Assets
Assets	528.6	496.1
Continuing Operations | Operating Segments | D&S West
Revenues from External Customers and Long-Lived Assets
Assets	414.9	420.3
Continuing Operations | Operating Segments | E&C Cryogenics
Revenues from External Customers and Long-Lived Assets
Assets	430.3	455.0
Continuing Operations | Operating Segments | E&C FinFans
Revenues from External Customers and Long-Lived Assets
Assets	1,028.0	434.2
Continuing Operations | Corporate
Revenues from External Customers and Long-Lived Assets
Assets	$ 79.6	$ 92.1