Noncontrolling Interests Redeemable interest in property partnerships (narrative) (Details) (Consolidated Properties [Member], Fountain Square [Member], Noncontrolling Interests [Member], USD $)	0 Months Ended
Oct. 04, 2012
Consolidated Properties [Member] \| Fountain Square [Member] \| Noncontrolling Interests [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Aggregate purchase price	$ 385,000,000
Debt recorded upon consolidation	211,300,000
Ownership Percentage	50.00%
Consideration paid	87,000,000
Ownership Percentage by Parent	50.00%
Future Fixed Price to Acquire Remaining Portion of Joint venture	$ 102,000,000
Fixed Price Option Expiration Date	Jan. 31, 2016

Aggregate purchase price

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- Definition

Fixed Price Option Expiration Date

+ References

No definition available.

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- Definition

Future Fixed Price to Acquire Remaining Portion of Joint venture

+ References

No definition available.

+ Details

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- Definition

Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=39739317&loc=d3e4845-128472

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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