Acquisitions (Third Quarter 2016) - Additional Information (Detail) - Ed Jacobs & Associates Inc [Member] $ in Millions	9 Months Ended
Sep. 30, 2016 USD ($)
Business Acquisition, Contingent Consideration [Line Items]
Effective date of acquisition	Jul. 01, 2016
Acquired entity, name	Ed Jacobs & Associates, Inc.
Annual revenue	$ 2.1

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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Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e845-128460

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Name of the acquired entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 805
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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