Leases - Additional Information (Detail) - Capital Lease Obligations [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Capital Leased Assets [Line Items]
Depreciation on capital leases	$ 0.5	$ 0.5
Capital Lease One [Member]
Capital Leased Assets [Line Items]
Capital lease terms	24 Months
Capital Lease Two [Member]
Capital Leased Assets [Line Items]
Capital lease terms	36 Months
Computer Equipment and Leasehold Improvements [Member]
Capital Leased Assets [Line Items]
Assets purchased, financed by a capital lease	$ 1.0	$ 0.6

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.

No definition available.

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

A general description of the lessee's leasing arrangements including, but not limited to, the following: a) the basis on which contingent rental payments are determined; (b) the existence and terms of renewal or purchase options and escalation clauses; (c) restrictions imposed by lease agreements, such as those concerning dividends, additional debt, and further leasing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 25
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6394851&loc=SL2265659-115463

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 15
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=51672649&loc=d3e32400-112679

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6452660&loc=d3e36991-112694

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- Definition

Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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