Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 4,043	$ 4,150
Accumulated Amortization	(3,336)	(3,399)
Net Carrying Amount	$ 707	$ 751
Weighted Average Remaining Useful Life	16 years 6 months	16 years 3 months 18 days
Customer Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 2,499	$ 2,564
Accumulated Amortization	(2,499)	(2,564)
Brands Associated with Acquired Cell Lines [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	515	529
Accumulated Amortization	(151)	(153)
Net Carrying Amount	$ 364	$ 376
Weighted Average Remaining Useful Life	28 years 3 months 18 days	28 years 4 months 24 days
Product Licenses [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 867	$ 890
Accumulated Amortization	(524)	(515)
Net Carrying Amount	$ 343	$ 375
Weighted Average Remaining Useful Life	4 years	4 years 2 months 12 days
Other Intangibles [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 162	$ 167
Accumulated Amortization	$ (162)	$ (167)