Summary of Significant Accounting Policies - Property, Plant and Equipment (Details)	9 Months Ended
	Oct. 31, 2015
Buildings and building equipment | Minimum
Property and equipment amortized over the estimated useful life of related assets
Property and equipment, useful life	20 years
Buildings and building equipment | Maximum
Property and equipment amortized over the estimated useful life of related assets
Property and equipment, useful life	45 years
Computer hardware, software and equipment | Minimum
Property and equipment amortized over the estimated useful life of related assets
Property and equipment, useful life	3 years
Computer hardware, software and equipment | Maximum
Property and equipment amortized over the estimated useful life of related assets
Property and equipment, useful life	10 years
Furniture and fixtures
Property and equipment amortized over the estimated useful life of related assets
Property and equipment, useful life	10 years