Schedule of Fair Value of Pensions Plan Assets by Asset Category (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	$ 282,129	$ 302,899
Fixed Income Securities | Corporate Debt Securities
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	156,860	157,263
Fixed Income Securities | US Government Debt Securities
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	62,555	82,674
Fixed Income Securities | U.K. Government Securities
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	19,610	8,593
Fixed Income Securities | Asset-backed Securities
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	2,919	2,042
U.S. Equity (Large Cap)
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	21,309	23,832
International Equity
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	14,803	23,990
Guarantee Annuity Contract
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	2,985	3,108
Other
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	906	839
Cash and Cash Equivalents
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	182	558
Quoted Prices in Active Markets for Identical Instruments (Level 1)
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	21,561	23,712
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Fixed Income Securities | US Government Debt Securities
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	21,415	23,712
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Cash and Cash Equivalents
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	146
Significant Other Observable Inputs (Level 2)
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	260,568	279,187
Significant Other Observable Inputs (Level 2) | Fixed Income Securities | Corporate Debt Securities
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	156,860	157,263
Significant Other Observable Inputs (Level 2) | Fixed Income Securities | US Government Debt Securities
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	41,140	58,962
Significant Other Observable Inputs (Level 2) | Fixed Income Securities | U.K. Government Securities
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	19,610	8,593
Significant Other Observable Inputs (Level 2) | Fixed Income Securities | Asset-backed Securities
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	2,919	2,042
Significant Other Observable Inputs (Level 2) | U.S. Equity (Large Cap)
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	21,309	23,832
Significant Other Observable Inputs (Level 2) | International Equity
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	14,803	23,990
Significant Other Observable Inputs (Level 2) | Guarantee Annuity Contract
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	2,985	3,108
Significant Other Observable Inputs (Level 2) | Other
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	906	839
Significant Other Observable Inputs (Level 2) | Cash and Cash Equivalents
Schedule of Pension Plan Assets by Fair Value [Line Items]
Total	$ 36	$ 558