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Assets Measured at Fair Value on Recurring Basis for Pension Plan (Detail) - Pension Plans - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on recurring basis | $ 87,194 | $ 86,744
Equity Funds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on recurring basis | 40,124 | 42,760
Fixed Income Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on recurring basis | 32,192 | 31,136
Equity And Debt Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on recurring basis | 5,527 | 4,676
Fair Value, Inputs, Level 1 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on recurring basis | 77,843 | 78,572
Fair Value, Inputs, Level 1 | Equity Funds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on recurring basis | 40,124 | 42,760
Fair Value, Inputs, Level 1 | Fixed Income Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on recurring basis | 32,192 | 31,136
Fair Value, Inputs, Level 1 | Equity And Debt Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on recurring basis | 5,527 | 4,676
Fair Value, Inputs, Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on recurring basis | 9,351 | 8,172
Real Estate Funds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on recurring basis | 9,351 | 8,172
Real Estate Funds | Fair Value, Inputs, Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on recurring basis | $ 9,351 | $ 8,172

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- Definition This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a recurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. + References No definition available. + Details
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