Maximum length of time to maturity for instruments included as cash equivalents.

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- Definition

Summary of basis of presentation and significant accounting policies.

+ References

No definition available.

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- Definition

Trading securities sales

+ References

No definition available.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
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- Definition

Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27357-111563

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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- Definition

Amount of gain (loss) realized from securities classified as trading.

+ References

No definition available.

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Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) - USD ($) shares in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2018
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Maximum maturity period of cash and cash equivalent	three months
Trading Securities, Realized Gain (Loss)		$ 4,980
Trading Securities Sales	$ 0
Potential equivalent common stock excluded	5.4	10.6
Trading securities		$ 0	$ 0
Other Income, Net [Member]
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Unrealized gain (loss), trading securities	$ 0	$ 52,741
Minimum [Member]
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Vesting period for stock options	1 year
Maximum [Member]
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Vesting period for stock options	3 years