Cash, Cash Equivalents and Investments - Summary of Available-for-sale Securities' Adjusted Cost, Gross Unrealized Gains, Gross Unrealized Losses and Fair Value by Significant Investment Category (Details) $ in Thousands |
Mar. 31, 2018
USD ($)
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|---|---|
| Schedule of Available-for-sale Securities [Line Items] | |
| Adjusted Cost | $ 312,681 |
| Unrealized Losses | (16) |
| Fair Value | 312,665 |
| Money market funds | |
| Schedule of Available-for-sale Securities [Line Items] | |
| Adjusted Cost | 105,865 |
| Unrealized Losses | 0 |
| Fair Value | 105,865 |
| Commercial paper | |
| Schedule of Available-for-sale Securities [Line Items] | |
| Adjusted Cost | 194,384 |
| Unrealized Losses | (1) |
| Fair Value | 194,383 |
| Corporate debt securities | |
| Schedule of Available-for-sale Securities [Line Items] | |
| Adjusted Cost | 12,432 |
| Unrealized Losses | (15) |
| Fair Value | $ 12,417 |
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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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