Distribution Agreement, Additional Term

No definition available.

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- Definition

Distribution Agreement, Number Of Additional Terms

+ References

No definition available.

+ Details

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- 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

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

+ Details

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- Definition

Amount of increase (decrease) in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from adjustments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

+ Details

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

+ References

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- Details

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- Details

Name:	us-gaap_MajorCustomersAxis=astm_CarticelAndMACIDistributorMember
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Data Type:	na
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- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueNetMember
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Balance Type:
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- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_AccountsReceivableMember
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Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_MajorCustomersAxis=astm_LargestCustomerMember
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- Details

Name:	us-gaap_MajorCustomersAxis=astm_SecondLargestCustomerMember
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Period Type:

- Details

Name:	us-gaap_CounterpartyNameAxis=astm_OrsiniPharmaceuticalservicesInc.Member
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- Details

Name:	us-gaap_ValuationAllowancesAndReservesTypeAxis=us-gaap_AllowanceForReceivableFromInsuranceProviderMember
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- Details

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- Details

Name:	astm_ValuationAllowancesAndReservesPeriodAxis=astm_ValuationAllowancesAndReservesPeriodRelatedTo2017Member
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Balance Type:
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- Details

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REVENUE (Details) $ in Millions			3 Months Ended			6 Months Ended
REVENUE (Details) $ in Millions	Jun. 30, 2017	May 15, 2017 term	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Customer concentration \| Carticel And MACI Distributor \| Revenue
CONCENTRATION
Concentration risk			14.00%
Customer concentration \| Carticel And MACI Distributor \| Accounts Receivable
CONCENTRATION
Concentration risk	17.00%
Customer concentration \| Largest Customer \| Revenue
CONCENTRATION
Concentration risk					69.00%		65.00%
Customer concentration \| Second Largest Customer \| Revenue
CONCENTRATION
Concentration risk			11.00%		13.00%	14.00%	15.00%
Orsini
CONCENTRATION
Distribution agreement, number of additional terms \| term		2
Distribution agreement, additional term		2 years
Allowance for Receivable from Insurance Provider \| Valuation Allowances And Reserves Period, Related To 2016
CONCENTRATION
Revenue reserves, deductions				$ 2.1
Allowance for Receivable from Insurance Provider \| Valuation Allowances And Reserves Period, Related To 2017
CONCENTRATION
Revenue reserves, deductions				$ 0.7
Allowance for Receivable from Insurance Provider \| Valuation Allowances And Reserves Period, Related To 2017 \| Disputes
CONCENTRATION
Revenue reserves, reversal of change in estimate			$ 1.4