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Employee Benefit Plans (Deferred Compensation Plans) - Fair Value of Assets Held by Trust and Amounts Payable to Plan Participants (Detail) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Long-term Investments | $ 18,256 | $ 19,883
Amounts Payable to Plan Participants Non-current Liabilities | 18,256 | 19,883
Deferred Compensation Plan Assets [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Long-term investments | 18,256 | 19,883
Non-Current Liabilities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Amounts Payable to Plan Participants Non-current Liabilities | $ 18,256 | $ 19,883

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References No definition available. + Details
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- Definition Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer). + References No definition available. + Details
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- Definition Carrying amount as of the balance sheet date of assets held under deferred compensation agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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