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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.

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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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The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Amount of increase (decrease) in income that would have been recognized in previous periods if the adjustments to provisional amounts were recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of cash outflow, not made soon after acquisition date of business combination, to settle contingent consideration liability up to amount recognized at acquisition date, including, but not limited to, measurement period adjustment and less amount paid soon after acquisition date.

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BUSINESS ACQUISITIONS - Narrative (Details) € in Millions, £ in Millions					3 Months Ended
	Apr. 29, 2019 EUR (€)	Apr. 29, 2019 USD ($)	Apr. 03, 2018 USD ($)	Jan. 11, 2018 USD ($)	Mar. 30, 2019 USD ($)	Mar. 30, 2019 GBP (£)	Mar. 31, 2018 USD ($)	Sep. 29, 2018 USD ($)	Sep. 29, 2018 GBP (£)	Mar. 26, 2018 USD ($)	Jan. 11, 2018 GBP (£)
Credit facility \| $2.3 Billion Credit Facility
Business Acquisition [Line Items]
Credit facility										$ 2,300,000,000.0
Citoxlab
Business Acquisition [Line Items]
Integration related costs and transaction costs					$ 5,200,000
MPI Research
Business Acquisition [Line Items]
Purchase price			$ 829,700,000
Integration related costs and transaction costs					100,000		$ 2,700,000
Purchase price allocation			800,800,000
Cash acquired			27,700,000
Adjustments related to prior period			1,200,000
Goodwill, amount expected to be deductible for tax purposes			$ 4,100,000
Weighted average amortization life of intangible assets acquired			12 years
MPI Research \| Client relationships
Business Acquisition [Line Items]
Weighted average amortization life of intangible assets acquired			13 years
KWS BioTest Limited
Business Acquisition [Line Items]
Purchase price				$ 20,300,000
Integration related costs and transaction costs					100,000		400,000
Purchase price allocation				21,529,000
Cash acquired				1,000,000
Adjustments related to prior period				$ 400,000
Undiscounted contingent payments								$ 2,600,000	£ 2.0		£ 3.0
Payments for contingent liabilities					$ 2,600,000	£ 2.0
KWS BioTest Limited \| Client relationships
Business Acquisition [Line Items]
Weighted average amortization life of intangible assets acquired					12 years	12 years
Depreciation and Amortization Expense \| MPI Research
Business Acquisition [Line Items]
Adjustments related to prior period							6,900,000
Interest expense \| MPI Research
Business Acquisition [Line Items]
Adjustments related to prior period							$ 2,600,000
Subsequent Event \| Citoxlab
Business Acquisition [Line Items]
Purchase price	€ 448	$ 500,000,000