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Investments - Summary of Available-for-Sale Investments (Detail) $ in Thousands | Dec. 31, 2017 USD ($)
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Debt Securities, Available-for-sale [Line Items] |
Adjusted Cost | $ 89,683
Gross Unrealized (Losses) | (412)
Estimated Fair Value | 89,271
Certificates of Deposit [Member] |
Debt Securities, Available-for-sale [Line Items] |
Adjusted Cost | 4,915
Gross Unrealized (Losses) | (3)
Estimated Fair Value | 4,912
Municipal Securities [Member] |
Debt Securities, Available-for-sale [Line Items] |
Adjusted Cost | 84,768
Gross Unrealized (Losses) | (409)
Estimated Fair Value | $ 84,359

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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References No definition available. + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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- Definition Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer. + References No definition available. + Details
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