Employee Benefit Plans (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012 retirement_plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Cost recognized	$ 1,004	$ 773
Number of plans merged		2
Payments for postemployment benefits		1,997
Amounts that will be amortized from accumulated other comprehensive income (loss) in next fiscal year		228
Plan amendments		1,165
Curtailments		79
Amortization of prior service cost (credit)		79
Requisite service period	5 years
Accrued expenses	8,282	5,220
Effect On Accumulated Benefit Obligation And Service And Interest Cost [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Ultimate trend rate		1.00%
Equity Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations	62.00%
Debt Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations	26.00%
Equity Securities, Other [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations	12.00%
Debt Category Concentration [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations	10.00%
Post Retirement Benefit Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Number of participants	327
Age of non-union employees on September 1, 2012 for which certain benefits terminated, less than		60 years
Plan amendments	0	1,165
Minimum age of participant to become eligible for benefits	62 years
Age up to which health benefits continuation paid	65 years
Age at which company pays lump sum advance premium	65 years
Accrued expenses	405	604
Medicare Part D Subsidy Receipts [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated future employer contributions in next fiscal year	29
Increase In Health Care Cost Trend [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Effect of one percentage point increase (decrease) in assumed health care costs	263
Decrease In Health Care Cost Trend [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Effect of one percentage point increase (decrease) in assumed health care costs	(238)
Increase In Service And Interest Cost [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Effect of one percentage point increase (decrease) in assumed health care costs	24
Decrease In Service And Interest Cost [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Effect of one percentage point increase (decrease) in assumed health care costs	(21)
Minimum [Member] | Debt Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations	80.00%
Minimum [Member] | Percentage Variance From Established Investment Category Targets [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations	10.00%
Health Care Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan amendments		1,021
Life Insurance [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan amendments		$ 144