Schedule II - Valuation and Qualifying Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended										12 Months Ended
	Dec. 31, 2012 Accounts receivable-allowance for doubtful accounts [Member]	Dec. 31, 2011 Accounts receivable-allowance for doubtful accounts [Member]	Dec. 31, 2010 Accounts receivable-allowance for doubtful accounts [Member]	Dec. 31, 2012 Inventory-reserve for slow-moving items [Member]	Dec. 31, 2011 Inventory-reserve for slow-moving items [Member]	Dec. 31, 2010 Inventory-reserve for slow-moving items [Member]	Dec. 31, 2012 Notes receivable-allowance for doubtful accounts [Member]	Dec. 31, 2011 Notes receivable-allowance for doubtful accounts [Member]	Dec. 31, 2010 Notes receivable-allowance for doubtful accounts [Member]	Dec. 31, 2009 Notes receivable-allowance for doubtful accounts [Member]	Dec. 31, 2012 Deferred tax assets-valuation allowance [Member]	Dec. 31, 2011 Deferred tax assets-valuation allowance [Member]	Dec. 31, 2010 Deferred tax assets-valuation allowance [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 955	$ 636	$ 676	$ 1,767	$ 1,616	$ 1,198	$ 970	$ 970	$ 970	$ 970	$ 344	$ 310	$ 358
Additions-Charges to Costs and Expenses	(214)	347	145	181	751	485						34
Deductions-Write-offs/Costs Incurred	105	28	185	130	600	67					71		48
Balance at End of Year	$ 636	$ 955	$ 636	$ 1,818	$ 1,767	$ 1,616	$ 970	$ 970	$ 970	$ 970	$ 273	$ 344	$ 310