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.

No definition available.

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- Definition

Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

+ Details

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- Definition

Aggregate dividends declared during the period for each share of preferred stock outstanding.

+ References

No definition available.

+ Details

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Stockholders' Equity (Dividends Declared) (Details) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
	Apr. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Dividends declared		$ 240.2	$ 161.4	$ 163.6
Series A Preferred Stock [Member]
Class of Stock [Line Items]
Dividends declared		$ 28.0	$ 28.0	$ 28.0
Dividends declared, per share amount (USD per share)		$ 70.00	$ 70.00	$ 70.00
Dividend Rate in Effect		7.00%
Series C Preferred Stock [Member]
Class of Stock [Line Items]
Dividends declared		$ 36.0	$ 36.0	$ 36.0
Dividends declared, per share amount (USD per share)		$ 60.00	$ 60.00	$ 60.00
Dividend Rate in Effect		6.00%
Series D Preferred Stock [Member]
Class of Stock [Line Items]
Dividends declared		$ 44.6	$ 44.6	$ 44.6
Dividends declared, per share amount (USD per share)		$ 59.52	$ 59.52	$ 59.52
Dividend Rate in Effect		5.95%
Series E Preferred Stock [Member]
Class of Stock [Line Items]
Dividends declared		$ 27.8	$ 27.8	$ 27.8
Dividends declared, per share amount (USD per share)		$ 4,625.00	$ 4,625.00	$ 4,625.00
Dividend Rate in Effect		4.625%
Series F Preferred Stock [Member]
Class of Stock [Line Items]
Dividends declared		$ 25.0	$ 25.0	$ 27.2
Dividends declared, per share amount (USD per share)		$ 5,000.00	$ 5,000.00	$ 5,430.56
Dividend Rate in Effect		5.00%
Series G Preferred Stock [Member]
Class of Stock [Line Items]
Dividends declared		$ 78.8
Dividends declared, per share amount (USD per share)		$ 3,150.35
Dividend Rate in Effect	5.375%	5.375%