v3.6.0.2
Discontinued Operations - Additional Information (Detail) - USD ($)
 3 Months Ended 12 Months Ended
Aug. 04, 2015
Sep. 30, 2015
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]          
Current liabilities of discontinued operations       $ 15,313,000  
Fiber Optic Licensing Division [Member]          
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]          
Sales price of fiber optic licensing operations $ 1,000,000,000        
Net cash proceeds from sale of fiber optic licensing operations $ 848,000,000        
Gain on disposal of discontinued operations before taxes   $ 272,000,000   271,833,000  
Tax amount from gain loss of disposal of discontinued operations   101,000,000      
Gain on sale, Net of tax   $ 171,000,000      
Assets of fiber optic licensing operations     $ 0 0  
Current liabilities of discontinued operations     0    
Non-current liabilities of discontinued operations     0 $ 0  
Telecommunications [Member]          
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]          
Legal fees     1,000,000   $ 1,000,000
Legal fees, net of tax impact     $ 700,000   $ 600,000