Business Segment, Geographic Area, Product and Significant Customer Information - Reconciliation of Segment Assets to Consolidated Total Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated total assets	$ 3,381,948	$ 2,614,246
Other current assets	80,303	65,790
Property, plant and equipment, net	230,649	194,367
Other assets	44,228	38,682
Operating Segments [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated total assets	793,027	680,143
Segment Reconciling Items [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents and investments	470,321	728,461
Other current assets	80,303	65,790
Property, plant and equipment, net	230,649	194,367
Right-of-use asset	68,631
Goodwill and intangible assets, net	1,658,039	906,803
Other assets	44,228	$ 38,682
Assets classified as held for sale	$ 36,750

Cash and cash equivalents restricted cash and investments.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of other assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

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Carrying amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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