Debt Instrument, Basis Spread On Base Rate

No definition available.

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- Definition

Debt Instrument, Collateral, Number Of Leased Offices And Industrial Properties

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Maximum Distribution, Percentage of FFO

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Maximum Distribution Under Exemption, Percentage Of FFO

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Number Of States In Which Mortgaged Properties Are Located

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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

- Definition

Line of Credit Facility, Commitment Fee Percentage, Threshold, Unused Capacity as a Percentage of Current Capacity

+ References

No definition available.

+ Details

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- Definition

Line Of Credit Facility, Increase (Decrease) In Maximum Borrowing Capacity

+ References

No definition available.

+ Details

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

- Definition

Line Of Credit Facility, Number Of Extensions

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Line of Credit Facility, Accordion Feature, Increase Limit

+ References

No definition available.

+ Details

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Namespace Prefix:	gnl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Extension Term

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Unused Capacity, Facility Fee Multiplier

+ 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

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://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

Reference 2: 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 3: 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(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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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

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- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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Credit Facilities - Credit Facility (Details) € in Millions					1 Months Ended
Credit Facilities - Credit Facility (Details) € in Millions	Apr. 12, 2019 leased_office_and_industrial_property	Jul. 02, 2018 USD ($)	Jul. 02, 2018 EUR (€)	Jul. 24, 2017 USD ($) extension	Apr. 30, 2019 sate	Jun. 30, 2019 USD ($)	Jun. 30, 2019 EUR (€)	Dec. 31, 2018 USD ($)
Line of Credit Facility [Line Items]
Borrowings outstanding						$ 259,527,000		$ 363,894,000
Maximum distribution as percentage of FFO					95.00%
Maximum distribution as percentage of FFO, under exception					100.00%
Column Financial, Inc. and Societe Generale Financial Corporation
Line of Credit Facility [Line Items]
Number of states in which mortgaged properties are located (state) \| sate					12
Credit Facility
Line of Credit Facility [Line Items]
Weighted-average effective interest rate						2.60%	2.60%
Credit Facility \| Federal Funds
Line of Credit Facility [Line Items]
Basis spread on base rate determination				0.50%
Credit Facility \| LIBOR
Line of Credit Facility [Line Items]
Basis spread on base rate determination				1.00%
Credit Facility \| LIBOR \| Minimum
Line of Credit Facility [Line Items]
Interest rate spread				1.60%
Credit Facility \| LIBOR \| Maximum
Line of Credit Facility [Line Items]
Interest rate spread				2.20%
Credit Facility \| Base Rate \| Minimum
Line of Credit Facility [Line Items]
Interest rate spread				0.60%
Credit Facility \| Base Rate \| Maximum
Line of Credit Facility [Line Items]
Interest rate spread				1.20%
Credit Facility \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Available for future borrowings						$ 90,700,000
Borrowings outstanding						259,500,000
Credit Facility \| Term Loan
Line of Credit Facility [Line Items]
Borrowings outstanding						277,400,000
Credit Facility \| KeyBank National Association \| Unsecured debt
Line of Credit Facility [Line Items]
Maximum borrowing capacity				$ 725,000,000.0		906,200,000
Increase in aggregate commitments		$ 35,600,000
Total line of credit commitment		950,000,000.0
Number of extensions \| extension				1
Extension term				1 year
Credit Facility \| KeyBank National Association \| Unsecured debt \| Minimum
Line of Credit Facility [Line Items]
Maximum borrowing capacity		722,200,000
Credit Facility \| KeyBank National Association \| Unsecured debt \| Maximum
Line of Credit Facility [Line Items]
Maximum borrowing capacity		914,400,000
Credit Facility \| KeyBank National Association \| Unsecured debt \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity						632,000,000.0
Increase in maximum borrowing capacity		132,000,000.0
Facility fee multiplier				0.0030
Borrowings outstanding						259,527,000		$ 363,894,000
Credit Facility \| KeyBank National Association \| Unsecured debt \| Revolving Credit Facility \| Above Threshold
Line of Credit Facility [Line Items]
Unused capacity commitment fee				0.25%
Commitment fee percentage				50.00%
Credit Facility \| KeyBank National Association \| Unsecured debt \| Revolving Credit Facility \| Below Threshold
Line of Credit Facility [Line Items]
Unused capacity commitment fee				0.15%
Commitment fee percentage				50.00%
Credit Facility \| KeyBank National Association \| Unsecured debt \| Term Loan Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity						$ 280,300,000	€ 246.5
Increase in maximum borrowing capacity		$ 60,200,000	€ 51.8
Multi-Tenant Mortgage Loan IV \| Column Financial, Inc. and Societe Generale Financial Corporation
Line of Credit Facility [Line Items]
Collateral, number of leased offices and industrial properties \| leased_office_and_industrial_property	16