Debt Instrument, Fixed Interest, Percent Of Principal Amount Covered By Derivative Instrument

No definition available.

Name:	gnl_DebtInstrumentFixedInterestPercentOfPrincipalAmountCoveredByDerivativeInstrument
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Data Type:	num:percentItemType
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Period Type:	duration

- Definition

Debt Instrument, Variable Interest, Percent Of Principal Amount Covered By Derivative Instrument

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Number of Real Estate Properties, Encumbered

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- 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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Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
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+ Details

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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

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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+ Details

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

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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

- Definition

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

+ References

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Balance Type:	credit
Period Type:	duration

- 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

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Mortgage Notes Payable, Net - Schedule of Long-term Debt Instruments (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) property	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) property	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Mortgage notes payable, net	$ 974,515		$ 974,515		$ 984,876
Loss on extinguishment of debt	$ 2,612	$ 0	$ 3,897	$ 0
Mortgage notes payable
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	87		87
Term Loan	$ 983,634		$ 983,634		992,344
Mortgage discount	(696)		(696)		(1,927)
Deferred financing costs, net of accumulated amortization	(8,423)		(8,423)		(5,541)
Mortgage notes payable, net	$ 974,515		$ 974,515		984,876
Effective Interest Rate	2.90%		2.90%
Mortgage notes payable \| Quest Diagnostics \| LIBOR
Debt Instrument [Line Items]
Interest rate spread			2.00%
Mortgage notes payable \| EUR
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	22		22
Term Loan	$ 377,860		$ 377,860		390,215
Mortgage notes payable \| EUR \| Finnair
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	4		4
Term Loan	$ 32,957		$ 32,957		34,022
Effective Interest Rate	2.20%		2.20%
Mortgage notes payable \| EUR \| Tokmanni
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 33,625		$ 33,625		34,711
Effective Interest Rate	2.40%		2.40%
Mortgage notes payable \| EUR \| Auchan
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 9,632		$ 9,632		9,943
Effective Interest Rate	1.70%		1.70%
Mortgage notes payable \| EUR \| Pole Emploi
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 6,731		$ 6,731		6,948
Effective Interest Rate	1.70%		1.70%
Mortgage notes payable \| EUR \| Sagemcom
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 41,661		$ 41,661		43,006
Effective Interest Rate	1.70%		1.70%
Mortgage notes payable \| EUR \| Worldline
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 5,802		$ 5,802		5,990
Effective Interest Rate	1.90%		1.90%
Mortgage notes payable \| EUR \| DCNS
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 11,024		$ 11,024		11,381
Effective Interest Rate	1.50%		1.50%
Mortgage notes payable \| EUR \| ID Logistics II
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	2		2
Term Loan	$ 12,185		$ 12,185		12,578
Effective Interest Rate	1.30%		1.30%
Mortgage notes payable \| EUR \| Rheinmetall
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 12,301		$ 12,301		12,698
Effective Interest Rate	2.60%		2.60%
Mortgage notes payable \| EUR \| OBI DIY
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 5,222		$ 5,222		5,391
Effective Interest Rate	2.40%		2.40%
Mortgage notes payable \| EUR \| RWE AG
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	3		3
Term Loan	$ 72,529		$ 72,529		74,872
Effective Interest Rate	1.60%		1.60%
Mortgage notes payable \| EUR \| Rexam
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 5,959		$ 5,959		6,301
Effective Interest Rate	1.80%		1.80%
Mortgage notes payable \| EUR \| Metro Tonic
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 30,752		$ 30,752		31,746
Effective Interest Rate	1.70%		1.70%
Mortgage notes payable \| EUR \| ID Logistics I
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 4,642		$ 4,642		4,792
Effective Interest Rate	1.00%		1.00%
Mortgage notes payable \| EUR \| DB Luxembourg
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 41,777		$ 41,777		43,126
Effective Interest Rate	1.40%		1.40%
Mortgage notes payable \| EUR \| ING Amsterdam
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 51,061		$ 51,061		52,710
Effective Interest Rate	1.70%		1.70%
Mortgage notes payable \| GBP
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	43		43
Term Loan	$ 299,674		$ 299,674		301,141
Fixed interest, percent of principal amount covered by derivative instrument			80.00%
Mortgage notes payable \| GBP \| LIBOR
Debt Instrument [Line Items]
Variable interest, percent of principal amount covered by derivative instrument			20.00%
Mortgage notes payable \| GBP \| McDonald's
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		1,025
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Wickes Building Supplies I
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		2,226
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Everything Everywhere
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		5,397
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Thames Water
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		8,096
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Wickes Building Supplies II
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		2,626
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Northern Rock
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		7,084
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Wickes Building Supplies III
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		2,564
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Provident Financial
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		17,203
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Crown Crest
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		25,973
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Aviva
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		21,183
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Bradford & Bingley
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		10,200
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Intier Automotive Interiors
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		6,375
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Capgemini
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		6,381
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Fujitsu
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		33,435
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Amcor Packaging
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		4,218
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Fife Council
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		2,474
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Malthrust
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		4,318
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Talk Talk
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		5,161
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| HBOS
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		7,272
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| DFS Trading
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		13,680
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| DFS Trading
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		3,203
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| HP Enterprise Services
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		12,531
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Foster Wheeler
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		53,026
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| Harper Collins
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		37,880
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| NCR Dundee
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		7,610
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| GBP \| UK Multi-Property Cross Collateralized Loan
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	43		43
Term Loan	$ 299,674		$ 299,674		0
Effective Interest Rate	3.20%		3.20%
Mortgage notes payable \| USD
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	22		22
Term Loan	$ 306,100		$ 306,100		300,988
Mortgage notes payable \| USD \| Quest Diagnostics
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 52,800		$ 52,800		52,800
Effective Interest Rate	4.20%		4.20%
Mortgage notes payable \| USD \| Western Digital
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		17,363
Effective Interest Rate	0.00%		0.00%
Loss on extinguishment of debt			$ 1,300
Mortgage notes payable \| USD \| AT&T Services
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	1		1
Term Loan	$ 33,550		$ 33,550		33,550
Effective Interest Rate	2.00%		2.00%
Mortgage notes payable \| USD \| AT&T Services \| Adjusted LIBOR
Debt Instrument [Line Items]
Interest rate spread			2.00%
Mortgage notes payable \| USD \| FedEx Freight
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		6,165
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| USD \| Veolia Water
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	0		0
Term Loan	$ 0		$ 0		4,110
Effective Interest Rate	0.00%		0.00%
Mortgage notes payable \| USD \| Multi-Tenant Mortgage Loan I
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	12		12
Term Loan	$ 187,000		$ 187,000		187,000
Effective Interest Rate	4.40%		4.40%
Mortgage notes payable \| USD \| Multi-Tenant Mortgage Loan II
Debt Instrument [Line Items]
Encumbered Properties (property) \| property	8		8
Term Loan	$ 32,750		$ 32,750		$ 0
Effective Interest Rate	4.40%		4.40%