Sale of ownership interest percentage.

No definition available.

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- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of gain (loss) from deconsolidation of subsidiary and derecognition of group of assets constituting transfer of business or nonprofit activity, excluding conveyance of oil and gas mineral rights and transfer of good or service in contract with customer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4582445-111684

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Cash received for the sale of real estate that is not part of an investing activity during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3179-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Subsequent Events (Details) - USD ($) $ in Thousands	Jul. 21, 2020	Jun. 30, 2020	Dec. 31, 2019
Subsequent Event [Line Items]
Debt, net		$ 2,201,755
Secured Debt
Subsequent Event [Line Items]
Debt, net		$ 310,155	$ 313,812
Subsequent Event \| Philadelphia - Office
Subsequent Event [Line Items]
Sale of ownership interest percentage	30.00%
Sale price of property sold	$ 115,000
Net proceeds	100,800
Fair vaue adjustment upon deconsolidation	270,000
Subsequent Event \| Philadelphia - Office \| Secured Debt
Subsequent Event [Line Items]
Debt, net	222,100
Preferred Equity Interest In One Commerce Square and Two Commerce Square \| Subsequent Event \| Philadelphia - Office
Subsequent Event [Line Items]
Equity commitment	20,000
Preferred Equity Interest In One Commerce Square and Two Commerce Square \| Investor In One Commerce Square And Two Commerce Square \| Subsequent Event \| Philadelphia - Office
Subsequent Event [Line Items]
Equity commitment	$ 20,000