Summary of Significant Accounting Policies - Intangibles (Details) - USD ($) $ in Millions	Jan. 31, 2019	Jan. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 85.5	$ 88.2
Accumulated Amortization	(24.5)	(21.5)
Product Rights
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	48.9	48.9
Accumulated Amortization	(16.0)	(13.5)
Key Money Deposits
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	34.1	36.8
Accumulated Amortization	(6.0)	(5.5)
Trademarks
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2.5	2.5
Accumulated Amortization	$ (2.5)	$ (2.5)