Annual base rents.

No definition available.

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- Definition

Interest rate on deferred rent amount outstanding.

+ References

No definition available.

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- Definition

Investment Activity.

+ References

No definition available.

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- Definition

Lease termination date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
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- Definition

Number of lease renewal.

+ References

No definition available.

+ Details

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

- Definition

Number of properties to lease.

+ References

No definition available.

+ Details

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Namespace Prefix:	mrt_
Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Number of skilled nursing facilities.

+ References

No definition available.

+ Details

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Namespace Prefix:	mrt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Operating leases term of lease.

+ References

No definition available.

+ Details

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Namespace Prefix:	mrt_
Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

Percentage of annual escalators.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Percentage of real estate property investment.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 1
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- Definition

Amount of expense incurred and directly related to generating revenue from leased and rented property or equipment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Term of lessor's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
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- Definition

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

+ References

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- Definition

The total amount of lease revenue recognized for the period for which the lessee was obligated under leasing arrangements regardless of any other events or conditions. This amount excludes contingent revenue and sublease revenue.

+ References

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- Definition

The amount of the monthly rental payments due under the lease entered into in connection with the transactions involving the sale of property to another party and the lease of the property back to the seller.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77913982&loc=d3e50796-112755

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Balance Type:	credit
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- Definition

Difference between actual rental income due and rental income recognized on a straight-line basis.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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Investment Activity - Additional Information (Details) $ in Thousands		1 Months Ended	3 Months Ended	12 Months Ended
	Jul. 31, 2017 Facility	Nov. 30, 2018 USD ($) Lease Facility	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($) Property	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Oct. 06, 2018 USD ($)	Aug. 09, 2017
Investment Activity [Line Items]
Percentage of annual escalators								8.75%
Percentage of total real estate property investments				100.00%	100.00%
Rental income				$ 52,701	$ 58,913	$ 48,330
Rent reserved for non-cash straight-line rent outstanding				936	5,919	(3,447)
Property-related expenses				2,797	$ 1,482	$ 1,303
Fundamental Healthcare
Investment Activity [Line Items]
Total base rent				$ 8,800
Number of properties to lease \| Property				4
Deferred rent				$ 1,700
Interest rate on deferred rent amount outstanding				9.00%
Mountains Edge Hospital \| Fundamental Healthcare
Investment Activity [Line Items]
Deferred rent							$ 2,400
Texas
Investment Activity [Line Items]
Percentage of total real estate property investments				50.20%	53.30%
Real Estate Investment
Investment Activity [Line Items]
Initial term of lease	15 years
Number of skilled nursing facilities \| Facility	2
Percentage of annual escalators	9.00%
Real Estate Investment \| Texas
Investment Activity [Line Items]
Monthly base rent due under the master lease				$ 1,100	$ 1,100
Total base rent				12,900
Rental income				6,900
Rent reserved for non-cash straight-line rent outstanding			$ 4,800
Property-related expenses				$ 1,500
Creative Solutions \| Real Estate Investment \| Texas
Investment Activity [Line Items]
Initial term of lease		15 years		15 years
Number of skilled nursing facilities \| Facility		10
Annual base rent		$ 7,700		$ 7,700
Percentage of annual escalators		2.00%
Number of lease renewal options \| Lease		2
Lease renewal term		5 years
Percentage of total real estate property investments				24.20%
Prior Texas Ten Tenant \| Real Estate Investment \| Texas
Investment Activity [Line Items]
Lease termination date				Dec. 31, 2018