Segment Information (Narrative) (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) segment	Jun. 30, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment			2
PIRM
Segment Reporting Information [Line Items]
Segment reporting intercompany revenue	$ 1.7	$ 1.6	$ 3.2	$ 3.0
Segment reporting intercompany expense	0.8	0.7	1.6	1.5
UWS
Segment Reporting Information [Line Items]
Segment reporting intercompany revenue	0.8	0.7	1.6	1.5
Segment reporting intercompany expense	$ 1.7	$ 1.6	$ 3.2	$ 3.0