Special Charges Changes in Accrued Special Charges (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Restructuring Cost and Reserve
Restructuring Reserve	$ 3,006	$ 4,517	$ 7,846
Special charges	15,769	45,081	23,490
Payments for Restructuring	(12,368)	(46,592)	(26,819)
Restructuring Reserve	6,407	3,006	4,517
Restructuring Reserve, Noncurrent			252
Restructuring Reserve, Current	6,407	3,006	4,265
Employee Severance
Restructuring Cost and Reserve
Restructuring Reserve	1,935	370	1,004
Special charges	6,791	13,496	3,535
Payments for Restructuring	(4,587)	(11,931)	(4,169)
Restructuring Reserve	$ 4,139	$ 1,935	$ 370
Percentage of termination benefit paid	42.00%	86.00%	90.00%
Merger Costs [Member]
Restructuring Cost and Reserve
Restructuring Reserve	$ 0
Special charges	5,553	$ 0	$ 0
Payments for Restructuring	(4,168)
Restructuring Reserve	1,385	0
Litigation Costs
Restructuring Cost and Reserve
Restructuring Reserve	311	3,406	4,855
Special charges	1,465	4,118	18,408
Payments for Restructuring	(1,381)	(7,213)	(19,857)
Restructuring Reserve	395	311	3,406
Other Restructuring
Restructuring Cost and Reserve
Restructuring Reserve	760	741	1,987
Special charges	1,960	2,235	1,547
Payments for Restructuring	(2,232)	(2,216)	(2,793)
Restructuring Reserve	488	760	741
Early Retirement Benefits [Member]
Restructuring Cost and Reserve
Restructuring Reserve	0	0
Special charges	$ 0	25,232	0
Payments for Restructuring		(25,232)
Restructuring Reserve		$ 0	$ 0

Percentage of termination benefit paid as of the balance sheet date.

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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 420
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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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