Class Of Warrant Or Right, Term

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- Definition

Debt Instrument, Covenant, Amount Outstanding Under Agreement, Percent, Minimum

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- Definition

Restricted Cash and Investments, Minimum Amount

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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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.

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- Definition

Amount of cash equivalents restricted as to withdrawal or usage. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 50
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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(1)(a))
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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Feb. 28, 2015	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial assets fair value		$ 40,942		$ 38,080
Expected life		3 years 9 months 18 days	4 years 1 month 1 day
Volatility		41.00%	35.00%
Restricted cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial assets fair value		$ 4,045		$ 1,630
Warrants issued by Rhapsody \| Related Party Debt Obligation
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total expected term for warrant	10 years
Napster [Member] \| Restricted cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Restricted Cash Equivalents		1,900
Restricted Cash and Investments, Minimum Amount		$ 1,500
Napster [Member] \| Related Party Debt Obligation
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Covenant, Amount Outstanding Under Agreement, Percent, Minimum		5.00%