Debt Instrument, Debt Default, Interest

No definition available.

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- Definition

Debt Instrument, Extension Option Fee, Percent

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Number of Extension Options

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Term, Extension Option

+ References

No definition available.

+ Details

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- Definition

Line Of Credit Facility, Accordion Feature, Increase Limit

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Represents the number of buildings secured by mortgage notes.

+ References

No definition available.

+ Details

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- Definition

Represents the number of properties secured by mortgage notes.

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ References

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

-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=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

+ Details

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

- Definition

The average effective interest rate during the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Period Type:	instant

- 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.

+ References

No definition available.

+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 50

-Section 40

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Name Accounting Standards Codification

-Topic 470

-SubTopic 50

-Section 40

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629

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Balance Type:	credit
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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

-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=6876686&loc=d3e534808-122878

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-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

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Balance Type:	na
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. 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/presentationRef

-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=6876686&loc=d3e534808-122878

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.22)

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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

+ Details

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

- Definition

Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(d))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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Balance Type:	debit
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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

+ Details

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- Details

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- Details

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Indebtedness - Narrative (Details)							3 Months Ended		9 Months Ended		12 Months Ended	15 Months Ended
Indebtedness - Narrative (Details)	Aug. 03, 2015 USD ($)	Jun. 05, 2015 USD ($)	Jun. 03, 2015 USD ($)	May. 01, 2015 USD ($)	Jan. 29, 2015 USD ($) option	Jan. 28, 2015 USD ($)	Sep. 30, 2015 USD ($) property building	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) property building	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2015 USD ($) property building
Debt Instrument [Line Items]
(Loss) gain on early extinguishment of debt							$ (3,887,000)	$ 6,699,000	$ 6,111,000	$ 6,699,000
Real estate properties, net							3,088,158,000		3,088,158,000		$ 4,697,998,000	$ 3,088,158,000
Mortgage notes payable, net							367,713,000		$ 367,713,000		$ 609,249,000	367,713,000
Revolving credit facility
Debt Instrument [Line Items]
Interest rate payable percentage									1.44%
Amount outstanding							0		$ 0			0
Revolving credit facility \| Minimum
Debt Instrument [Line Items]
Commitment fee percentage					0.125%
Revolving credit facility \| Maximum
Debt Instrument [Line Items]
Commitment fee percentage					0.30%
Revolving credit facility \| LIBOR
Debt Instrument [Line Items]
Basis points on variable rate									1.25%
Revolving credit facility \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis points on variable rate					0.875%
Revolving credit facility \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis points on variable rate					1.55%
Revolving credit facility \| Base rate \| Minimum
Debt Instrument [Line Items]
Basis points on variable rate					0.00%
Revolving credit facility \| Base rate \| Maximum
Debt Instrument [Line Items]
Basis points on variable rate					0.55%
Unsecured term loan, due December 2016
Debt Instrument [Line Items]
Basis points on variable rate											1.85%
Outstanding indebtedness						$ 400,000,000
Unsecured revolving credit facility \| Revolving credit facility
Debt Instrument [Line Items]
Maximum borrowing capacity					$ 750,000,000.0	$ 750,000,000.0
Basis points on variable rate											1.50%
Commitment fee percentage						0.35%
(Loss) gain on early extinguishment of debt									$ (400,000)
Debt instrument, number of extension options \| option					2
Debt instrument, extension option term					6 months
Debt instrument, extension option fee, percent					0.075%
Amount available for borrowing							750,000,000.0		750,000,000.0			750,000,000.0
Unsecured revolving credit facility \| Letter of credit
Debt Instrument [Line Items]
Maximum borrowing capacity					$ 100,000,000.0
Loan facility, 5-year term
Debt Instrument [Line Items]
Term loan amount outstanding					$ 200,000,000.0		200,000,000		$ 200,000,000			200,000,000
Interest accrual rate									1.59%
Loan facility, 5-year term \| LIBOR
Debt Instrument [Line Items]
Basis points on variable rate									1.40%
Loan facility, 5-year term \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis points on variable rate					0.90%
Loan facility, 5-year term \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis points on variable rate					1.80%
Loan facility, 5-year term \| Revolving credit facility
Debt Instrument [Line Items]
Debt instrument, term					5 years
Loan facility, 7-year term
Debt Instrument [Line Items]
Term loan amount outstanding					$ 200,000,000.0		$ 200,000,000		$ 200,000,000			$ 200,000,000
Interest accrual rate									1.99%
Loan facility, 7-year term \| LIBOR
Debt Instrument [Line Items]
Basis points on variable rate									1.80%
Loan facility, 7-year term \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis points on variable rate					1.40%
Loan facility, 7-year term \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis points on variable rate					2.35%
Loan facility, 7-year term \| Revolving credit facility
Debt Instrument [Line Items]
Debt instrument, term					7 years
Revolving credit facility and term loans
Debt Instrument [Line Items]
Additional increases in maximum amount of borrowings available					$ 1,150,000,000.00
5.75% unsecured senior notes due 2015
Debt Instrument [Line Items]
(Loss) gain on early extinguishment of debt				$ (100,000)
Amount of debt, redeemed, defeased, or prepaid				$ 138,800,000
Interest rate stated percentage				5.75%
Mortgage notes
Debt Instrument [Line Items]
Number of real estate properties secured by mortgage \| property							6		6			6
Number of buildings secured by mortgage \| building							10		10			10
Real estate properties, net							$ 452,400,000		$ 452,400,000			$ 452,400,000
Mortgage notes payable, net							367,700,000		367,700,000			367,700,000
Mortgage notes \| 225 Water Street in Jacksonville, Florida
Debt Instrument [Line Items]
Outstanding indebtedness							40,100,000		40,100,000			$ 40,100,000
(Loss) gain on early extinguishment of debt									17,300,000
Interest accrual rate												10.03%
Default interest												4.00%
Mortgage notes \| 1320 Main Street
Debt Instrument [Line Items]
(Loss) gain on early extinguishment of debt									(6,200,000)
Amount of debt, redeemed, defeased, or prepaid			$ 38,700,000
Mortgage notes \| 111 East Wacker Drive
Debt Instrument [Line Items]
(Loss) gain on early extinguishment of debt							$ (3,900,000)		(3,900,000)
Amount of debt, redeemed, defeased, or prepaid	$ 141,400,000
7.36% Mortgage Debt \| 2501 20th Place South
Debt Instrument [Line Items]
(Loss) gain on early extinguishment of debt									$ (600,000)
Amount of debt, redeemed, defeased, or prepaid		$ 10,000,000
Interest rate stated percentage		7.36%