Debt instrument aggregate principal amount redeemed.

No definition available.

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- Definition

Land purchase obligations.

+ References

No definition available.

+ Details

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

- Definition

Number of cemetery divested.

+ References

No definition available.

+ Details

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

- Definition

Number of crematories divested.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Number of funeral home divested.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Percentage of remaining net proceeds from asset disposition to be used for debt redemption.

+ References

No definition available.

+ Details

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

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 (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228

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

- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4582445-111684

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Balance Type:	credit
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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3179-108585

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

- Definition

This element represents the cash inflow during the period from the sale of a component of the entity.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

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DIVESTITURES - Additional Information (Detail) $ in Thousands			1 Months Ended	9 Months Ended
	Apr. 07, 2020 USD ($)	Jan. 03, 2020 USD ($) Property	Mar. 31, 2020 USD ($) Property	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Aggregate cash purchase price				$ 48,336	$ 1,250
Gain on sale of businesses				31,120
Senior Secured Notes
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Percentage of remaining net proceeds from asset disposition to redeem additional portion of debt			80.00%
Remaining California Sale \| Senior Secured Notes
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Aggregate principal amount of debt redeemed from assets dispositions			$ 3,200
Oakmont Agreement
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of cemetery divested \| Property		1
Number of funeral home divested \| Property		1
Gain on sale of businesses				24,400
Oakmont Agreement \| Oakmont Sale
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Aggregate cash purchase price		$ 33,000
Oakmont Agreement \| Oakmont Sale \| Senior Secured Notes
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Aggregate principal amount of debt redeemed from assets dispositions		$ 30,300
Olivet Agreement
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Aggregate principal amount of debt redeemed from assets dispositions	$ 20,500
Land purchase obligations	17,100
Olivet Agreement \| Olivet Sale
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain on sale of businesses				7,200
Aggregate purchase price	$ 24,300
California Agreement
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of cemetery divested \| Property			5
Number of funeral home divested \| Property			6
Number of crematories divested \| Property			4
California Agreement \| Remaining California Sale
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Aggregate cash purchase price			$ 7,100
Impairment charge				$ 2,200