FAIR VALUE MEASUREMENTS - Available-for-Sale Investments Included in Cash Equivalents (Details) - Cash and Cash Equivalents - USD ($) $ in Thousands |
Mar. 31, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Debt Securities, Available-for-sale [Line Items] | ||
| Adjusted Cost | $ 85,993 | $ 85,363 |
| Gross Unrealized Losses | (16) | (33) |
| Fair Value | 85,977 | 85,330 |
| Municipal bonds and notes | ||
| Debt Securities, Available-for-sale [Line Items] | ||
| Adjusted Cost | 4,188 | 12,149 |
| Gross Unrealized Losses | 0 | (7) |
| Fair Value | 4,188 | 12,142 |
| Corporate debt securities | ||
| Debt Securities, Available-for-sale [Line Items] | ||
| Adjusted Cost | 48,535 | 51,862 |
| Gross Unrealized Losses | (16) | (26) |
| Fair Value | 48,519 | 51,836 |
| Financial institution instruments | ||
| Debt Securities, Available-for-sale [Line Items] | ||
| Adjusted Cost | 33,270 | 21,352 |
| Gross Unrealized Losses | 0 | 0 |
| Fair Value | $ 33,270 | $ 21,352 |
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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. No definition available.
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- Definition Amount before tax of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. No definition available.
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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. No definition available.
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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. No definition available.
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