The dollar value amount approved to issue common stock under an At-the-Market Offering program.

No definition available.

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- Definition

The remaining dollar value amount approved to issue common stock under an At-the-Market program

+ References

No definition available.

+ Details

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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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.

+ References

No definition available.

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- Definition

Number of new stock issued during the period.

+ References

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- Definition

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

+ References

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Stockholders' Equity (At-the-Market Offering Program) (Details) - USD ($) $ / shares in Units, $ in Millions						12 Months Ended
	Nov. 19, 2018	Aug. 03, 2018	May 29, 2018	Sep. 12, 2017	May 05, 2017	Dec. 31, 2018	Dec. 31, 2017	Jun. 14, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, Value of Shares Approved for Future Issuance								$ 1,000.0
Common Stock, Shares Authorized						$ 660.0
Stock Issued During Period, Shares, New Issues	46,000,000	43,700,000	34,500,000	28,200,000	24,500,000
Stock Issued During Period, Value, New Issues	$ 786.0	$ 817.0	$ 633.0	$ 577.0	$ 503.0	$ 2,611.0	$ 1,238.0
Sale of Stock, Price Per Share	$ 17.09	$ 18.68	$ 18.35	$ 20.47	$ 20.51	$ 18.03	$ 20.96
Common Stock At The Market Sale Agreement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, New Issues						20,773,191	7,570,296
Stock Issued During Period, Value, New Issues						$ 375.4	$ 158.7