Business Segment, Geographic, and Concentration Risk Information - Summary of Depreciation, Amortization and Assets by Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Total depreciation and amortization
Total consolidated depreciation and amortization	$ 3,673	$ 2,026	$ 888
Total assets:
Total assets	140,413	105,890
Oncology Innovation Platform
Total depreciation and amortization
Total consolidated depreciation and amortization	482	195	101
Total assets:
Total assets	65,966	53,022
Global Supply Chain Platform
Total depreciation and amortization
Total consolidated depreciation and amortization	2,272	1,644	$ 787
Total assets:
Total assets	51,128	48,560
Commercial Platform
Total depreciation and amortization
Total consolidated depreciation and amortization	919	187
Total assets:
Total assets	$ 23,319	$ 4,308