Leases Leases Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019 USD ($)
Lessee, Lease, Description [Line Items]
Renewal term	5 years
Termination period	1 year
Operating lease expense	$ 6.3
Variable lease cost	$ 1.1
Minimum
Lessee, Lease, Description [Line Items]
Remaining lease terms	1 year
Maximum
Lessee, Lease, Description [Line Items]
Remaining lease terms	13 years