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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Earnings Per Share (Anti-dilutive Shares) (Details) shares in Thousands	12 Months Ended
	Dec. 31, 2019 shares	Dec. 31, 2018 shares	Dec. 31, 2017 trading_day shares
Joint venture shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares	0	0	255
Series J convertible perpetual preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares	0	15,704	15,635
Unvested Time Based Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares			6
Market-based Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares			17
3.125% senior convertible notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stated interest rate (percent)	3.125%		3.125%
Threshold consecutive trading days \| trading_day			40