Pension Plan (Detail) - Schedule of Net Benefit Costs (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Interest cost	$ 130	$ 137	$ 260	$ 274
Expected return on plan assets	(109)	(99)	(219)	(198)
Amortization of net actuarial loss	121	87	242	174
Net periodic pension cost	$ 142	$ 125	$ 283	$ 250