Leases (Operating Lease Payment Schedule) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Sep. 30, 2019
Leases [Abstract]
Lessee, operating lease, payment due current year	$ 10.7
Lessee, operating lease, payment due year two	10.7
Lessee, operating lease, payment due year three	8.1
Lessee, operating lease, payment due year four	6.7
Lessee, operating lease, payment due year five	5.3
Lessee, operating lease, payment due after year five	42.4
Lessee, operating lease, payments due	83.9
Lessee, operating lease, undiscounted excess amount	28.3
Operating lease, liability	$ 55.6
Operating leases, future minimum payments due, next twelve months		$ 13.6
Operating leases, future minimum payments, due in two years		10.5
Operating leases, future minimum payments, due in three years		7.4
Operating leases, future minimum payments, due in four years		5.9
Operating leases, future minimum payments, due in five years		4.6
Operating leases, future minimum payments, due thereafter		12.5
Operating leases, future minimum payments, due		$ 54.5