Expected Future Benefit Payments of Pension and Other Post-Retirement Benefit Plans (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Pension Plans, Defined Benefit
Schedule of Pension and Other Postretirement Benefits Expected Benefit Payments [Line Items]
2014	$ 3,678
2015	3,783
2016	4,064
2017	4,312
2018	4,328
2019 to 2023	26,439
Other Post-Retirement Benefit Plans
Schedule of Pension and Other Postretirement Benefits Expected Benefit Payments [Line Items]
2014	151
2015	103
2016	92
2017	91
2018	79
2019 to 2023	$ 170