Stockholders' Equity (Preferred Stock) (Details) - $ / shares	Jun. 25, 2019	Jun. 30, 2020	Dec. 31, 2019
Stockholders' Equity Note [Abstract]
Preferred stock, shares authorized		5,000,000	5,000,000
Preferred stock, par value (in dollars per share)		$ 0.00001	$ 0.00001
Preferred stock, shares issued		0	0
Preferred stock, shares outstanding		0	0
2019 Rights Agreement
Class of Stock [Line Items]
Maximum days to register for resale shares held by investors	120 days

Maximum Days To Register For Resale Shares Held By Investors

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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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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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