Summary Of Significant Accounting Policies (Redeemable Noncontrolling Interests) (Details) - USD ($) $ in Thousands		12 Months Ended
Aug. 02, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Rollforward of Redeemable Noncontrolling Interests
Beginning balance		$ 136,208	$ 141,157
Contributions		9,961	354
Net income		3,430	3,865	$ 3,874
Distributions & Redemptions		(15,366)	(4,071)
Change in redemption value		5,525	(5,097)
Ending balance		$ 139,758	$ 136,208	$ 141,157
Montrose Crossing
Redeemable Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	10.10%
Purchase Price Under Option	$ 10,000
Ownership interest subsequent to redemption	100.00%

Ownership interest subsequent to redemption of noncontrolling interest.

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- Definition

Redeemable Noncontrolling Interests Contributions

+ References

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- Definition

Redeemable Noncontrolling Interests Distributions

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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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=116634182&loc=SL114868664-224227

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- Definition

The cash outflow during the period for redemption of redeemable noncontrolling interests.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

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As of the reporting date, the aggregate carrying amount 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 (16)(c)
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-Topic 480
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-Section S99
-Paragraph 3A
-Subparagraph 15
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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-Topic 480
-SubTopic 10
-Section S99
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-Subparagraph 14
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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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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Amount of increase (decrease) in temporary equity from changes classified as other.

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