Retirement Plans and Other Postretirement Benefits - Expected Amortization Expense (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013
Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Amortization of net actuarial loss	$ 648
Accretion of prior service cost	(280)
Other Post Retirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Amortization of net actuarial loss	23
Accretion of prior service cost	$ (20)

Amount included in accumulated other comprehensive income (AOCI) related to prior service cost (credit) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

No definition available.

Name:	us-gaap_DefinedBenefitPlanFutureAmortizationOfPriorServiceCostCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration