Property and Equipment - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property and equipment, cost	$ 1,024	$ 179
Property and equipment, accumulated amortization	175	90
Property and equipment, net book Value	849	89
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, cost	490	48
Property and equipment, accumulated amortization	77	42
Property and equipment, net book Value	413	6
Office Furniture, Equipment and Systems [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, cost	534	131
Property and equipment, accumulated amortization	98	48
Property and equipment, net book Value	$ 436	$ 83