Leases (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Lessee Lease Description [Line Items]
Operating leases, options to extend	some of which include options to extend the leases for up to an additional ten years.
Operating leases, existence of option to extend	true
Operating sublease, option to extend	certain subleases have renewal terms that can extend the lease for up to an additional two years.
Operating sublease, existence of option to extend	true
Operating lease not yet commenced, amount	$ 23.0
Operating lease not yet commenced, description	commence during 2020 with a lease term through 2031
Increase in right-of-use asset	$ 12.0
Increase in lease liability	12.0
Payments under operating lease agreement in 2019	16.6
Payments under operating lease agreement in 2020	14.1
Payments under operating lease agreement in 2021	13.1
Payments under operating lease agreement in 2022	11.5
Payments under operating lease agreement in 2023	9.6
Thereafter	$ 14.7
Operating Leases, Rent Expense		$ 19.0	$ 16.4
Maximum
Lessee Lease Description [Line Items]
Operating leases, remaining lease term	8 years
Operating leases, option to extend leases term	10 years
Operating subleases, remaining sublease term	4 years
Operating subleases, option to extend sublease term	2 years