Future Minimum Rental and Lease Payments (Detail) (USD $)	Dec. 31, 2012
Operating and Capital Leases [Line Items]
Operating Leases 2013	$ 4,570,000
Operating Leases 2014	4,508,000
Operating Leases 2015	4,265,000
Operating Leases 2016	3,409,000
Operating Leases 2017	1,650,000
Operating Leases Thereafter	530,000
Capital Leases 2013	338,000
Capital Leases 2014	248,000
Capital Leases 2015	248,000
Capital Leases 2016	248,000
Capital Leases 2017	0
Capital Leases Thereafter	0
Operating Leases, Total minimum lease payments	18,932,000
Capital Leases, Total minimum lease payments	1,082,000
Capital Lease Expense
Operating and Capital Leases [Line Items]
Less amount representing interest	83,000
Present value of minimum lease payments	999,000
Current portion	303,000
Long-term portion	$ 696,000