Redeemable Noncontrolling Interests (Schedule Of Changes In The Value Of The Redeemable Noncontrolling Interests) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Redeemable Noncontrolling Interest [Line Items]
Balance	$ 513,297
Income Attributed to Noncontrolling Interests	(6,471)	$ (6,471)
Redemption Value Adjustment	(8,441)	(9,571)
Balance	515,267
Redeemable Noncontrolling Interests [Member]
Redeemable Noncontrolling Interest [Line Items]
Balance	513,297	503,382
Net	513,297	503,382
Income Attributed to Noncontrolling Interests	6,471	6,471
Distributions	(6,471)	(6,471)
Redemption Value Adjustment	1,970	3,100
Balance	515,267	506,482
Redeemable Noncontrolling Interests [Member] \| Series A And Series A-1 Preferred Units In MCRLP [Member]
Redeemable Noncontrolling Interest [Line Items]
Balance	52,324	52,324
Net	52,324	52,324
Income Attributed to Noncontrolling Interests	455	455
Distributions	(455)	(455)
Balance	52,324	52,324
Rockpoint [Member] \| Redeemable Noncontrolling Interests [Member]
Redeemable Noncontrolling Interest [Line Items]
Balance	460,973	451,058
Net	460,973	451,058
Income Attributed to Noncontrolling Interests	6,016	6,016
Distributions	(6,016)	(6,016)
Redemption Value Adjustment	1,970	3,100
Balance	$ 462,943	$ 454,158

Redeemable Noncontrolling Interest Decrease From Distribution

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- Definition

Redeemable Noncontrolling Interest Redemption Value Adjustment

+ References

No definition available.

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- Definition

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.19)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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- Definition

The aggregate fair value as of the reporting date of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 14
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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-Publisher FASB
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-Topic 480
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-Section S99
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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

Value of new stock classified as temporary equity issued during the period.

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