Acquisition of C Technologies, Inc. (Fair Value of Net Assets Acquired) (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Accounts receivable	$ 3,044
Business combination, intangible assets	90,830
Goodwill	468,845	$ 326,735
C Technologies
Business Acquisition [Line Items]
Cash and cash equivalents	3,795
Restricted cash	26,933
Accounts receivable	3,044
Inventory	3,783
Prepaid expenses and other current assets	93
Fixed assets	40
Operating lease right of use asset	3,836
Business combination, intangible assets	90,800
Goodwill	142,903
Accounts payable	(436)
Accrued liabilities	(2,461)
Accrued bonus	(26,928)
Deferred revenue	(1,709)
Operating lease liability	(51)
Operating lease liability, long-term	(3,785)
Fair value of net assets acquired	239,887
C Technologies \| Customer relationships
Business Acquisition [Line Items]
Business combination, intangible assets	59,680
C Technologies \| Technology—developed
Business Acquisition [Line Items]
Business combination, intangible assets	28,920
C Technologies \| Trademark
Business Acquisition [Line Items]
Business combination, intangible assets	1,570
C Technologies \| Non-compete agreements
Business Acquisition [Line Items]
Business combination, intangible assets	$ 660

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