Estimated Useful Lives of Property and Equipment (Detail)	12 Months Ended
	Dec. 31, 2018
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property plant and equipment, estimated useful life	Term of lease
Capital Lease
Property Plant And Equipment [Line Items]
Property plant and equipment, estimated useful life	Term of lease
Minimum | Buildings and Building Improvements
Property Plant And Equipment [Line Items]
Property plant and equipment, estimated useful life	2 years
Minimum | Plant and Equipment
Property Plant And Equipment [Line Items]
Property plant and equipment, estimated useful life	1 year
Minimum | Production Tooling
Property Plant And Equipment [Line Items]
Property plant and equipment, estimated useful life	2 years
Minimum | Computer Equipment and Software
Property Plant And Equipment [Line Items]
Property plant and equipment, estimated useful life	1 year
Maximum | Buildings and Building Improvements
Property Plant And Equipment [Line Items]
Property plant and equipment, estimated useful life	50 years
Maximum | Plant and Equipment
Property Plant And Equipment [Line Items]
Property plant and equipment, estimated useful life	20 years
Maximum | Production Tooling
Property Plant And Equipment [Line Items]
Property plant and equipment, estimated useful life	7 years
Maximum | Computer Equipment and Software
Property Plant And Equipment [Line Items]
Property plant and equipment, estimated useful life	10 years