Acquisitions - Purchase Price Allocation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2017
Business Acquisition [Line Items]
Intangible assets subject to amortization	$ 171,113
Goodwill	439,452	$ 439,095	$ 454,612
Measurement period adjustments	5,142
Paragon Medical
Business Acquisition [Line Items]
Goodwill	$ 161,800

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The amount of identifiable intangible assets recognized as of the acquisition date.

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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.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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