Intangible Assets - Amortized Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 52,668	$ 47,280
Accumulated Amortization	44,356	40,965
Net Carrying Value	8,312	6,315
Distribution networks
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	38,060	38,060
Accumulated Amortization	37,422	35,051
Net Carrying Value	638	3,009
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	6,605	4,880
Accumulated Amortization	4,836	4,749
Net Carrying Value	1,769	131
Completed technologies
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	8,003	4,340
Accumulated Amortization	2,098	1,165
Net Carrying Value	$ 5,905	$ 3,175