Fair Value Measurements and Investments - Schedule of Change in Valuation of Securities (Detail) - Bone Biologics Inc [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Equity securities beginning balance	$ 219	$ 219	$ 2,768
Purchase of additional common stock	0	0	500
Fair value adjustments and impairments recognized in other expense	(219)		(4,678)
Equity securities ending balance		219	219
ASU 2016-01 [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Impact of adoption of ASU 2016-01 recognized in other income	$ 0	$ 0	$ 1,629