Pension and Employee Benefit Plans - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013 Age
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Effective date of retirement for availing post retirement health care plan	Jan. 01, 1990
Minimum age for the retirees to elect desired health care plan	65
Defined benefit plan contributions	$ 74
Pension plan [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Anticipated contribution to fund the pension plan during the reminder of the fiscal year	133
Health care plan [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Anticipated contribution to fund the pension plan during the reminder of the fiscal year	$ 8