Schedule II - Valuation and Qualifying Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for accounts receivable [Member]
Movement in Valuation Allowances and Reserves
Valuation Allowances and Reserves, Balance at beginning of period	$ 482	$ 1,382	$ 855
Valuation Allowances and Reserves, Additions charged to costs and expenses	730	1,045	1,244
Valuation Allowances and Reserves, Deductions	(595)	(1,945)	(717)
Valuation Allowances and Reserves, Balance at end of period	617	482	1,382
Allowance for excess and obsolete inventory [Member]
Movement in Valuation Allowances and Reserves
Valuation Allowances and Reserves, Balance at beginning of period	352	417	558
Valuation Allowances and Reserves, Additions charged to costs and expenses	76	73	158
Valuation Allowances and Reserves, Deductions	(127)	(138)	(299)
Valuation Allowances and Reserves, Balance at end of period	$ 301	$ 352	$ 417