Fair Value Measurements - Acquisition Related Obligations Level 3 (Detail) (Level 3 [Member], USD $) In Thousands, unless otherwise specified			6 Months Ended
Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Contingent consideration obligations [Member]	Jun. 30, 2014 Deferred consideration obligations [Member]
Business Acquisition, Contingent Consideration [Line Items]
Fair value at beginning of period	$ 2,023	$ 3,080
Changes in the fair value of acquisition consideration obligations			(34)
Payments of deferred consideration obligations				(1,023)
Fair value at the end of the period	$ 2,023	$ 3,080

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Amount of increase (decrease) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

+ Details

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