Consideration Paid for Entiera and Amounts for Assets Acquired and Liabilities Assumed (Detail) (Entiera Inc., USD $) In Thousands, unless otherwise specified	May 07, 2012
Business Acquisition [Line Items]
Cash	$ 18,390
Acquisition-related costs (included in the company's consolidated statement of income for the year ended September 30, 2012 as a component of restructuring and acquisition-related expense)	163
Cash and cash equivalents	138
Accounts receivable, net	546
Prepaid expenses and other current assets	153
Deferred income taxes	1,024
Property and equipment, net	100
Intangible assets
Other assets	24
Accounts payable	(725)
Other accrued liabilities	(152)
Deferred revenue	(254)
Total identifiable net assets	3,354
Goodwill	15,036
Total	18,390
Completed technology
Intangible assets
Intangible assets	2,200
Customer relationships
Intangible assets
Intangible assets	$ 300

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