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Business Acquisitions and Divestitures - Additional Information (Detail) - USD ($) $ in Thousands |  | 2 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jan. 08, 2016 | Apr. 30, 2018 | Jan. 31, 2018 | Mar. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Business Acquisition [Line Items] |  |  |  |  |  |
Goodwill |  |  |  | $ 1,055,737 | $ 1,038,346 | $ 1,057,214
Strategic Sourcing Excellence LLC |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Ownership percentage acquired | 51.00% |  |  |  |  |
Cash consideration to acquired certain assets and assumed certain liabilities | $ 2,550 |  |  |  |  |
Contingent earn-out consideration-High end | 20,000 |  |  |  |  |
Acquisition related cost | 164 |  |  |  |  |
Acquired assets | 327 |  |  |  |  |
Liabilities assumed | 617 |  |  |  |  |
Preliminary estimated purchase consideration | 14,490 |  |  |  |  |
Customer related intangible assets | $ 300 |  |  |  |  |
Acquired intangible assets, weighted average amortization period | 5 years |  |  |  |  |
Goodwill | $ 14,479 |  |  |  |  |
Strategic Sourcing Excellence LLC | If either the call or put option is exercised |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Equity method investment ownership percentage | 49.00% |  |  |  |  |
Strategic Sourcing Excellence LLC | If either the call or put option is exercised | Maximum |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Contingent earn-out consideration-High end | $ 9,800 |  |  |  |  |
Strategic Sourcing Excellence LLC | Call Option | Scenario, Forecast |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Equity method investment ownership percentage |  |  | 49.00% |  |  |
Strategic Sourcing Excellence LLC | Selling Equityholders Put Option | Scenario, Forecast |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Equity method investment ownership percentage |  | 49.00% |  |  |  |
Strategic Sourcing Excellence LLC | Selling Equityholders Put Option | Scenario, Forecast | Maximum |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Selling equity holders put option exercise price |  | $ 2,950 |  |  |  |
Strategic Sourcing Excellence LLC | Selling Equityholders Put Option | Scenario, Forecast | Minimum |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Selling equity holders put option exercise price |  | $ 2,450 |  |  |  |

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- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275 + Details
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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e1043-128460 + Details
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- Definition Amount of assets acquired at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472 + Details
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- Definition The amount of identifiable intangible assets recognized as of the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472 + Details
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- Definition Amount of liabilities assumed at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472 + Details
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- Definition Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472 + Details
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 + Details
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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266 + Details
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- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3213-108585 + Details
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