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 in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Goodwill Goodwill - Narrative (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill	$ 624,455		$ 454,612
Goodwill acquired during period	168,111
Total stockholders’ equity	641,034		$ 486,104
Paragon Medical Inc
Goodwill [Line Items]
Goodwill	162,438	$ 157,421
Bridgemedica, LLC
Goodwill [Line Items]
Goodwill acquired during period	8,000
Southern California Technical Arts, Inc.
Goodwill [Line Items]
Goodwill acquired during period	$ 2,700