Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables)

12 Months Ended

Jan. 31, 2017

Accounting Policies [Abstract]

Schedule Of Purchased Technology and Other Intangible Asset Amortization Expense

Total purchased technology and other intangible asset amortization expense was as follows:

Fiscal year ended January 31,	2017		2016		2015
Purchased technology and other intangible asset amortization expense	$	13,356	$	16,019	$	15,265

Schedule of Goodwill and Intangible Assets

As of January 31, 2017, the carrying value of goodwill and intangible assets was as follows:

As of January 31,	2017			2016
Goodwill	$	611,536		$	606,842
Purchased technology and in-process research and development, gross	$	162,213		$	158,102
Less: accumulated amortization	(145,652		)	(138,375		)
Purchased technology and in-process research and development, net	$	16,561		$	19,727
Other intangible assets, gross	$	108,690		$	105,162
Less: accumulated amortization	(93,438		)	(87,443		)
Other intangible assets, net	$	15,252		$	17,719

Schedule of Goodwill Activity

The following table summarizes goodwill activity:

Balance as of January 31, 2015	$	599,929
Acquisitions	8,500
Foreign exchange	(1,587		)
Balance as of January 31, 2016	$	606,842
Acquisitions	6,111
Foreign exchange	(1,417		)
Balance as of January 31, 2017	$	611,536

Schedule of Expected Amortization Expense

We estimate the aggregate amortization expense related to purchased technology and other intangible assets will be as follows:

Fiscal years ending January 31,
2018	$	12,845
2019	11,192
2020	4,432
2021	1,842
2022	1,102
Thereafter	400
Aggregate amortization expense	$	31,813

Schedule of Property Plant and Equipment Useful Lives

	Estimated Useful Lives (in years)
Buildings		40
Land improvements		20
Computer equipment and furniture	3	-	5
Leasehold improvements(1)	3	-	10

⁽¹⁾  Amortized over the shorter of the lease term or estimated life.

Property, Plant, and Equipment

A summary of property, plant, and equipment, net is as follows:

As of January 31,	2017			2016
Computer equipment and furniture	$	394,042		$	351,982
Buildings and building equipment	117,240			115,312
Land and improvements	24,610			21,489
Leasehold improvements	48,812			41,906
Property, plant, and equipment, gross	584,704			530,689
Less: accumulated depreciation and amortization	(374,024		)	(348,597		)
Property, plant, and equipment, net	$	210,680		$	182,092

Advertising Expense

Fiscal year ended January 31,	2017		2016		2015
Advertising expense	$	3,435	$	3,683	$	2,985