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Summary of Significant Accounting Policies - Additional Information (Detail) | 12 Months Ended
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Dec. 31, 2018
Accounting Policies [Abstract] |
Effective maturity of investments | 10 years
Maximum investment of the company in partnership | 5.00%
Building [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment, Useful Life | 39 years
Building Improvements [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment, Useful Life | 10 years
Computer Hardware and Software [Member] | Minimum [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment, Useful Life | 2 years
Computer Hardware and Software [Member] | Maximum [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment, Useful Life | 10 years
Manufacturing Test Equipment [Member] | Minimum [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment, Useful Life | 2 years
Manufacturing Test Equipment [Member] | Maximum [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment, Useful Life | 5 years
Furniture and Fixtures [Member] | Minimum [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment, Useful Life | 2 years
Furniture and Fixtures [Member] | Maximum [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment, Useful Life | 5 years

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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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