Business Combinations - Skaff Narratives (Details) - USD ($) $ in Millions		3 Months Ended
	Jan. 02, 2018	Mar. 31, 2019	Mar. 31, 2018
Business Acquisition
Payment for acquisition of businesses, net of cash acquired		$ 2.8	$ 12.5
Goodwill purchase price adjustment		18.7
Skaff
Business Acquisition
Voting percentage acquired	100.00%
Payment for acquisition of businesses, net of cash acquired	$ 12.5
Long-term deferred tax liabilities		0.8
Goodwill purchase price adjustment		$ 0.8