Amount of common stock authorized under equity distribution agreement.

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- Definition

Warrants exercised in shares.

+ References

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

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- Definition

Number of warrants or rights outstanding.

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- Definition

The cash inflow from the additional capital contribution to the entity.

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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

Number of new stock issued during the period.

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Common Stock and Related Matters - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2016	Sep. 20, 2018	Mar. 31, 2018	May 09, 2017
Securities Financing Transaction [Line Items]
Proceeds from issuance of common stock			$ 689,000,000.0
Warrants exercised (in shares)				19,983,843
Warrants remaining						99,888
Common Stock [Member]
Securities Financing Transaction [Line Items]
Issuance of common stock (in shares)			13,844,000
Exercise of warrants - share settled (in shares)				11,336,856		58,814
2017 ATM Program [Member]
Securities Financing Transaction [Line Items]
Amount of common stock authorized under equity distribution agreement							$ 750,000,000.0
Equity Distribution Agreement May 2017 [Member]
Securities Financing Transaction [Line Items]
Issuance of common stock (in shares)	0	0	7,527,902
Proceeds from issuance of common stock			$ 364,900,000
Amount of common stock authorized under equity distribution agreement	$ 382,100,000
2018 ATM Program [Member]
Securities Financing Transaction [Line Items]
Amount of common stock authorized under equity distribution agreement					$ 750,000,000.0
Equity Distribution Agreement September 2018 [Member]
Securities Financing Transaction [Line Items]
Issuance of common stock (in shares)	0	0
Amount of common stock authorized under equity distribution agreement	$ 750,000,000.0