Debt Instrument, Extended Term

No definition available.

Name:	gcnl_DebtInstrumentExtendedTerm
Namespace Prefix:	gcnl_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Interest-only Period

+ References

No definition available.

+ Details

Name:	gcnl_DebtInstrumentInterestonlyPeriod
Namespace Prefix:	gcnl_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Term, Including Extension

+ References

No definition available.

+ Details

Name:	gcnl_DebtInstrumentTermIncludingExtension
Namespace Prefix:	gcnl_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Accordion Feature, Borrowing Capacity Reduction, Increment

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityAccordionFeatureBorrowingCapacityReductionIncrement
Namespace Prefix:	gcnl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line of Credit Facility, Accordion Feature, Higher Borrowing Capacity Option

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityAccordionFeatureHigherBorrowingCapacityOption
Namespace Prefix:	gcnl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Accordion Feature, Increase Limit

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityAccordionFeatureIncreaseLimit
Namespace Prefix:	gcnl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Administrative Agent Fee

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityAdministrativeAgentFee
Namespace Prefix:	gcnl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line of Credit Facility, Borrowing Capacity, Minimum Increment

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityBorrowingCapacityMinimumIncrement
Namespace Prefix:	gcnl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Aggregate Maximum, Percentage of Total Asset Value

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantAggregateMaximumPercentageofTotalAssetValue
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Aggregate Maximum Unhedged Variable Rate Debt, Percent of Asset Value

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantAggregateMaximumUnhedgedVariableRateDebtPercentofAssetValue
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Investments in Mortgage Notes Receivable, Maximum Percentage of Total Asset Value

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantInvestmentsinMortgageNotesReceivableMaximumPercentageofTotalAssetValue
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Investments in Unconsolidated Affiliates, Maximum Percentage of Total Asset Value

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantInvestmentsinUnconsolidatedAffiliatesMaximumPercentageofTotalAssetValue
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Leases Assets Under Renovation, Maximum Percentage of Total Asset Value

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantLeasesAssetsUnderRenovationMaximumPercentageofTotalAssetValue
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Maximum Consolidated Leverage Ratio

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantMaximumConsolidatedLeverageRatio
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Maximum Consolidated Leverage Ratio After Material Acquisition

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantMaximumConsolidatedLeverageRatioAfterMaterialAcquisition
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Maximum Consolidated Leverage Ratio, Number of Quarters of Higher Maximum

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantMaximumConsolidatedLeverageRatioNumberofQuartersofHigherMaximum
Namespace Prefix:	gcnl_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Covenant, Maximum Payout Ratio

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantMaximumPayoutRatio
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Maximum Total Secured Debt Ratio

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantMaximumTotalSecuredDebtRatio
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Maximum Total Secured Debt Ratio, Increase

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantMaximumTotalSecuredDebtRatioIncrease
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Maximum Total Secured Debt Ratio, Periods of Increased Percentage

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantMaximumTotalSecuredDebtRatioPeriodsofIncreasedPercentage
Namespace Prefix:	gcnl_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Maximum Total Secured Recourse Debt Ratio

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantMaximumTotalSecuredRecourseDebtRatio
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Minimum Consolidated Fixed Charge Coverage Ratio

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantMinimumConsolidatedFixedChargeCoverageRatio
Namespace Prefix:	gcnl_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Minimum Unsecured Interest Coverage Ratio

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantMinimumUnsecuredInterestCoverageRatio
Namespace Prefix:	gcnl_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Pre-leased Assets Under Development, Maximum Percentage of Total Asset Value

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantPreleasedAssetsUnderDevelopmentMaximumPercentageofTotalAssetValue
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Tangible Net Worth

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantTangibleNetWorth
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Tangible Net Worth, Additional Percentage of Net Future Equity issuances

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantTangibleNetWorthAdditionalPercentageofNetFutureEquityissuances
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Tangible Net Worth, Reducing Percentage for Redemption Payments

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantTangibleNetWorthReducingPercentageforRedemptionPayments
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Tangible Net Worth, Value

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantTangibleNetWorthValue
Namespace Prefix:	gcnl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Unimproved Land, Maximum Percentage of Total Asset Value

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityCovenantUnimprovedLandMaximumPercentageofTotalAssetValue
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Minimum Borrowing Capacity

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditFacilityMinimumBorrowingCapacity
Namespace Prefix:	gcnl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit facility, Covenant, Maximum Pool Value Contributed by Pool Properties Subject to Ground Leases

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditfacilityCovenantMaximumPoolValueContributedbyPoolPropertiesSubjecttoGroundLeases
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit facility, Covenant, Maximum Pool Value Contributed by Poop Properties Under Development or Assets Under Renovation

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditfacilityCovenantMaximumPoolValueContributedbyPoopPropertiesUnderDevelopmentorAssetsUnderRenovation
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit facility, Covenant, Maximum Pool Value Contributed by Single Property or Tenant

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditfacilityCovenantMaximumPoolValueContributedbySinglePropertyorTenant
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit facility, Covenant, Maximum Unsecured Leverage Ratio

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditfacilityCovenantMaximumUnsecuredLeverageRatio
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit facility, Covenant, Minimum Aggregate Leasing Percentage

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditfacilityCovenantMinimumAggregateLeasingPercentage
Namespace Prefix:	gcnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit facility, Covenant, Minimum Pool Properties

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditfacilityCovenantMinimumPoolProperties
Namespace Prefix:	gcnl_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit facility, Covenant, Minimum Unsecured Coverage Ratio

+ References

No definition available.

+ Details

Name:	gcnl_LineofCreditfacilityCovenantMinimumUnsecuredCoverageRatio
Namespace Prefix:	gcnl_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

Reference 1: 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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

- 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=109500613&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=119400593&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=6876686&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=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow for loan origination associated cost which is usually collected through escrow.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

Name:	us-gaap_PaymentsOfLoanCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

+ Details

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

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ 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 (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

Name:	us-gaap_RepaymentsOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=gcnl_TermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LoansPayableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gcnl_A2023TermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gcnl_A2024TermLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gcnl_A2026TermLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gcnl_KeybankLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=srt_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_MortgagesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gcnl_BofAKeyBankLoanMember
Namespace Prefix:
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Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gcnl_AIGLoanIIMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_UnsecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gcnl_UnsecuredCreditFacilityJuly2015Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_BridgeLoanMember
Namespace Prefix:
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Period Type:

Debt - Narrative (Details)			6 Months Ended
Debt - Narrative (Details)	Apr. 30, 2019 USD ($)	Jul. 20, 2015 USD ($)	Jun. 30, 2019 USD ($) property quarter	Jun. 30, 2018 USD ($)	Sep. 30, 2019	Dec. 31, 2018 USD ($)	Mar. 29, 2016 USD ($)
Debt Instrument [Line Items]
Closing costs paid			$ 5,737,000	$ 45,000
Outstanding debt			$ 1,935,589,000			$ 1,353,531,000
Term Loan
Debt Instrument [Line Items]
Credit facility borrowing capacity		$ 1,140,000,000.00
Term Loans
Debt Instrument [Line Items]
Maximum increment to borrowing capacity available under accordion feature	$ 2,000,000,000.0
Minimum increments allowed under accordion feature	25,000,000
Maximum borrowing capacity available under accordion feature	25,000,000
Term Loans \| 2023 Term Loan
Debt Instrument [Line Items]
Credit facility borrowing capacity	$ 200,000,000
Initial debt instrument term	4 years
Debt instrument term, including extension	5 years
Term Loans \| 2024 Term Loan
Debt Instrument [Line Items]
Credit facility borrowing capacity	$ 400,000,000
Initial debt instrument term	5 years
Term Loans \| 2026 Term Loan
Debt Instrument [Line Items]
Credit facility borrowing capacity	$ 150,000,000
Initial debt instrument term	7 years
Term Loans \| Keybank Loans
Debt Instrument [Line Items]
Closing costs paid	$ 5,700,000
Annual administrative agent fee	25,000
Compliance requirement - maximum consolidated leverage ratio (percent)			60.00%
Compliance requirement - maximum consolidated leverage ratio after material acquisition (percent)			65.00%
Compliance requirement - consecutive quarters after material acquisition subject to higher consolidated leverage ratio \| quarter			4
Compliance requirement - minimum consolidated tangible net worth (percent)			75.00%
Compliance requirement - minimum consolidated tangible net worth			$ 2,000,000,000
Compliance requirement - additional net future equity issuances (percent)			75.00%
Compliance requirement - reduction for amount of payments used to redeem stock (percent)			75.00%
Compliance requirement - minimum consolidated fixed charge coverage ratio			1.50
Compliance requirement - maximum total secured debt ratio (percent)			40.00%
Compliance requirement - increase in maximum total secured coverage ratio after material acquisition (percent)			5.00%
Compliance requirement - number of quarters subject to higher maximum total secured coverage ratio after material acquisition \| quarter			4
Compliance requirement - minimum unsecured interest coverage ratio			2.00
Compliance requirement - maximum total secured recourse debt ratio (percent)			10.00%
Compliance requirement - maximum aggregate maximum unhedged variable rate debt (percent)			30.00%
Restrictions - maximum unimproved land as percentage of total asset value (percent)			5.00%
Restrictions - pre-leased developments under development as a percentage of total asset value, maximum (percent)			20.00%
Restrictions - investments in unconsolidated affiliates as percentage of total asset value, maximum (percent)			10.00%
Restrictions - investments in mortgage notes receivable as percentage of total asset value, maximum (percent)			15.00%
Restrictions - leased assets under renovation as percentage of total asset value, maximum (percent)			10.00%
Restrictions - Aggregate investment limitations as a percentage of total asset value, maximum (percent)			25.00%
Term Loans \| Keybank Loans \| Forecast
Debt Instrument [Line Items]
Compliance requirement - maximum payout ratio (percent)					95.00%
Term Loans \| Keybank Loans \| Minimum
Debt Instrument [Line Items]
Unused commitment fee (percent)			0.15%
Term Loans \| Keybank Loans \| Maximum
Debt Instrument [Line Items]
Unused commitment fee (percent)			0.20%
Mortgages \| BOA/KeyBank Loan
Debt Instrument [Line Items]
Initial debt instrument term			10 years
Proceeds from borrowings	250,000,000
Contractual stated interest rate (percent)			4.32%
Outstanding debt			$ 250,000,000
Mortgages \| AIG Loan II
Debt Instrument [Line Items]
Initial debt instrument term			10 years
Proceeds from borrowings	127,000,000
Contractual stated interest rate (percent)			4.15%
Outstanding debt			$ 127,000,000
Interest-only period			5 years
Unsecured Debt \| Unsecured Credit Facility
Debt Instrument [Line Items]
Credit facility borrowing capacity		$ 640,000,000.0
Initial debt instrument term		5 years
Unsecured Debt \| Term Loan
Debt Instrument [Line Items]
Credit facility borrowing capacity		$ 640,000,000.0					$ 715,000,000.0
Debt repaid	715,000,000
Line of Credit \| Unsecured Credit Facility
Debt Instrument [Line Items]
Credit facility borrowing capacity		1,140,000,000.00
Revolving Credit Facility \| Unsecured Credit Facility
Debt Instrument [Line Items]
Credit facility borrowing capacity		$ 500,000,000.0
Initial debt instrument term		4 years
Debt instrument extended term		1 year
Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Credit facility borrowing capacity	$ 750,000,000
Initial debt instrument term	3 years
Debt instrument extended term	1 year
Permitted incremental reduction in revolving commitment	$ 50,000,000
Minimum borrowing capacity permitted	150,000,000
Covenant - minimum pool properties \| property			15
Covenant -maximum pool value contributed by single pool property of tenant (percent)			15.00%
Covenant - maximum aggregate pool value to be contributed by pool properties subject to ground leases (percent)			15.00%
Covenant - maximum aggregate pool value to be contributed by pool properties under development (percent)			20.00%
Covenant - minimum aggregate leasing percentage (percent)			90.00%
Covenant - maximum unsecured leverage ratio (percent)			60.00%
Covenant - minimum unsecured interest coverage ratio			2.00
Revolving Credit Facility \| Swingline
Debt Instrument [Line Items]
Credit facility borrowing capacity	$ 125,000,000
Revolving Credit Facility \| Unsecured Debt
Debt Instrument [Line Items]
Credit facility borrowing capacity		$ 500,000,000.0