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Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (Recurring [Member], USD $) In Thousands, unless otherwise specified | Jun. 30, 2014 | Dec. 31, 2013
--- | --- | ---
Financial Assets |  |
Non-qualified retirement savings plan assets | $ 6,234 | $ 6,000
Derivatives |  | 1
Total Assets | 6,234 | 6,001
Financial Liabilities |  |
Contingent consideration | (3,548) | (4,425)
Derivatives | (224) | (1)
Total Liabilities | (3,772) | (4,426)
Level 1 [Member] |  |
Financial Assets |  |
Non-qualified retirement savings plan assets | 5,085 | 4,944
Derivatives |  |
Total Assets | 5,085 | 4,944
Financial Liabilities |  |
Contingent consideration |  |
Derivatives |  |
Total Liabilities |  |
Level 2 [Member] |  |
Financial Assets |  |
Non-qualified retirement savings plan assets | 1,149 | 1,056
Derivatives |  | 1
Total Assets | 1,149 | 1,057
Financial Liabilities |  |
Contingent consideration |  |
Derivatives | (224) | (1)
Total Liabilities | (224) | (1)
Level 3 [Member] |  |
Financial Assets |  |
Non-qualified retirement savings plan assets |  |
Derivatives |  |
Total Assets |  |
Financial Liabilities |  |
Contingent consideration | (3,548) | (4,425)
Derivatives |  |
Total Liabilities | $ (3,548) | $ (4,425)

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + 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 (a) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13495-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226008-175313 + Details
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