Discontinued Operations - Sale of Commercial Business - Schedule of Carrying Value of Assets and Liabilities Classified as Assets Held for Sale Relates to Commercial Business (Detail) $ in Thousands	Dec. 31, 2016 USD ($)
Current assets:
Total current assets held for sale	$ 33,295
Total long-term assets held for sale	9,135
Current liabilities:
Total current liabilities held for sale	57,538
Total long-term liabilities held for sale	25,673
Commercial Business [Member]
Current assets:
Accounts receivable, net	17,194
Inventory	14,554
Prepaid expenses and other current assets	1,547
Total current assets held for sale	33,295
Property and equipment, net	1,553
Intangible assets, net	3,977
Goodwill	3,605
Total long-term assets held for sale	9,135
Current liabilities:
Accounts payable, accrued expenses and other	21,312
Deferred revenues	36,226
Total current liabilities held for sale	57,538
Deferred revenues, net of current portion	25,673
Total long-term liabilities held for sale	$ 25,673