Summary of Significant Accounting Policies (Narrative) (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)	Jan. 02, 2019 USD ($)
Number of Reportable Segments	3
Operating Lease, Right-of-Use Asset	$ 1,882	$ 2,100
Operating Lease, Liability	$ 1,919	$ 2,100
Maximum term of short-term lease expensed via exemption	12 months