Related Party Transaction, Minimum Monthly Base Management Fee

No definition available.

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Namespace Prefix:	gnl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

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

- 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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- Details

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- Details

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- Details

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- Details

Name:	gnl_RelatedPartyTransactionsByCostStatusAxis=gnl_IncurredMember
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- Details

Name:	gnl_RelatedPartyTransactionsByCostStatusAxis=gnl_ForgivenMember
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Related Party Transactions - Schedule of Amount Contractually Due and Forgiven in Connection With Operation Related Services (Details) - USD ($)		3 Months Ended		6 Months Ended
	Jun. 02, 2015	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Advisor \| Amended Advisory Agreement
Related Party Transaction [Line Items]
Minimum monthly base management fee	$ 18,000,000.0
Advisor \| Variable Base Management Fee
Related Party Transaction [Line Items]
Related party expenses		$ 2,900,000	$ 2,200,000	$ 5,800,000	$ 4,400,000
Incurred
Related Party Transaction [Line Items]
Related party expenses		8,874,000	8,162,000	17,668,000	16,205,000
Forgiven
Related Party Transaction [Line Items]
Related party expenses		0	0	0	0
Payable
Related Party Transaction [Line Items]
Related party payable		0		0		$ 0
Nonrecurring Fees \| Fees on gain from sale of investments \| Incurred
Related Party Transaction [Line Items]
Related party expenses		0	0	0	0
Nonrecurring Fees \| Fees on gain from sale of investments \| Forgiven
Related Party Transaction [Line Items]
Related party expenses		0	0	0	0
Nonrecurring Fees \| Fees on gain from sale of investments \| Payable
Related Party Transaction [Line Items]
Related party payable		0		0		0
Recurring Fees \| Asset management fees \| Incurred
Related Party Transaction [Line Items]
Related party expenses		7,376,000	6,694,000	14,753,000	13,365,000
Recurring Fees \| Asset management fees \| Forgiven
Related Party Transaction [Line Items]
Related party expenses		0	0	0	0
Recurring Fees \| Asset management fees \| Payable
Related Party Transaction [Line Items]
Related party payable		0		0		0
Recurring Fees \| Property management fees \| Incurred
Related Party Transaction [Line Items]
Related party expenses		1,498,000	1,468,000	2,915,000	2,840,000
Recurring Fees \| Property management fees \| Forgiven
Related Party Transaction [Line Items]
Related party expenses		0	0	0	0
Recurring Fees \| Property management fees \| Payable
Related Party Transaction [Line Items]
Related party payable		0		0		0
Recurring Fees \| Incentive compensation \| Incurred
Related Party Transaction [Line Items]
Related party expenses		0	0	0	0
Recurring Fees \| Incentive compensation \| Forgiven
Related Party Transaction [Line Items]
Related party expenses		0	$ 0	0	0
Recurring Fees \| Incentive compensation \| Payable
Related Party Transaction [Line Items]
Related party payable		$ 0		0		$ 0
General and Administrative Expense \| Incurred
Related Party Transaction [Line Items]
Related party expenses				$ 500,000	$ 600,000