Segment Information - Company's Segments Information (Details) - USD ($) $ in Millions	3 Months Ended											12 Months Ended
	Jan. 31, 2016	[1]	Oct. 31, 2015	Jul. 31, 2015	[2]	Apr. 30, 2015	Jan. 31, 2015	Oct. 31, 2014	[3]	Jul. 31, 2014	Apr. 30, 2014	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Net sales:
Net sales	$ 1,213.6		$ 938.2	$ 990.5		$ 962.4	$ 1,285.3	$ 959.6		$ 992.9	$ 1,012.1	$ 4,104.9	$ 4,249.9	$ 4,031.1
Earnings (losses) from operations:
Segment Reporting Earnings Losses From Continuing Operations Before Unallocated Corporate Expenses Interest												958.9	1,028.5	934.6
Americas [Member]
Net sales:
Net sales												1,947.0	2,033.5	1,926.9
Earnings (losses) from operations:
Segment Reporting Earnings Losses From Continuing Operations Before Unallocated Corporate Expenses Interest												390.8	435.5	374.3
Asia-Pacific [Member]
Net sales:
Net sales												1,003.1	1,025.2	944.7
Earnings (losses) from operations:
Segment Reporting Earnings Losses From Continuing Operations Before Unallocated Corporate Expenses Interest												264.4	281.6	244.1
Japan [Member]
Net sales:
Net sales												541.3	554.3	578.6
Earnings (losses) from operations:
Segment Reporting Earnings Losses From Continuing Operations Before Unallocated Corporate Expenses Interest												199.9	196.0	215.6
Europe [Member]
Net sales:
Net sales												505.7	513.3	476.2
Earnings (losses) from operations:
Segment Reporting Earnings Losses From Continuing Operations Before Unallocated Corporate Expenses Interest												97.4	110.5	102.4
Reportable Geographical Components [Member]
Net sales:
Net sales												3,997.1	4,126.3	3,926.4
Earnings (losses) from operations:
Segment Reporting Earnings Losses From Continuing Operations Before Unallocated Corporate Expenses Interest												952.5	1,023.6	936.4
Other [Member]
Net sales:
Net sales												107.8	123.6	104.7
Earnings (losses) from operations:
Segment Reporting Earnings Losses From Continuing Operations Before Unallocated Corporate Expenses Interest												$ 6.4	$ 4.9	$ (1.8)

[1] On a pre-tax basis, includes charges for the quarter ended January 31, 2016 of: i.$28.3 million, which reduced net earnings per diluted share by $0.14, associated with an impairment charge related to a financing arrangement with Koidu Limited (see "Note B - Summary of Significant Accounting Policies" and "Note J - Commitments and Contingencies"); andii.$8.8 million, which reduced net earnings per diluted share by $0.04, associated with severance related to staffing reductions and subleasing of certain office space for which only a portion of the Company's future rent obligations will be recovered (see "Note J - Commitments and Contingencies").

[2] On a pre-tax basis, includes a charge of $9.6 million for the quarter ended July 31, 2015, which reduced net earnings per diluted share by $0.05, associated with an impairment charge related to a financing arrangement with Koidu Limited (see "Note B - Summary of Significant Accounting Policies" and "Note J - Commitments and Contingencies").

[3] On a pre-tax basis, includes a charge of $93.8 million for the quarter ended October 31, which reduced net earnings per diluted share by $0.47, associated with the redemption of $400.0 million in aggregate principal amount of the Private Placement Notes prior to their scheduled maturities (see "Note G - Debt").