Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenue, Major Customer [Line Items]
Provision for uncollectibles			$ (359,290)	$ (212,546)
Net revenue	$ 822,216	$ 650,227	$ 2,305,393	$ 1,862,622
Ambulatory Services [Member]
Revenue, Major Customer [Line Items]
Percentage of revenues from governmental healthcare programs			26.00%	26.00%
Net revenue	314,609	308,983	$ 941,490	$ 903,884
Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	619,740	370,675	1,596,901	1,059,017
Contract and other revenue	34,473	33,061	108,549	95,748
Provision for uncollectibles	(146,606)	(62,492)	(341,547)	(196,027)
Net revenue	507,607	341,244	1,363,903	958,738
Medicare [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	72,425	46,171	192,974	133,467
Medicaid [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	35,735	20,818	97,258	58,696
Commercial and Managed Care [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	403,859	256,593	1,065,583	731,192
Self-Pay [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	$ 107,721	$ 47,093	$ 241,086	$ 135,662
Sales Revenue, Net [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	100.00%	100.00%	100.00%	100.00%
Health Care Organization, Patient Service Revenue [Member] \| Sales Revenue, Net [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	122.00%	109.00%	117.00%	110.00%
Health Care Organization, Patient Service Revenue [Member] \| Sales Revenue, Net [Member] \| Medicare [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	14.00%	14.00%	14.00%	14.00%
Health Care Organization, Patient Service Revenue [Member] \| Sales Revenue, Net [Member] \| Medicaid [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	7.00%	6.00%	7.00%	6.00%
Health Care Organization, Patient Service Revenue [Member] \| Sales Revenue, Net [Member] \| Commercial and Managed Care [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	80.00%	75.00%	78.00%	76.00%
Health Care Organization, Patient Service Revenue [Member] \| Sales Revenue, Net [Member] \| Self-Pay [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	21.00%	14.00%	18.00%	14.00%
Contract and Other Revenue [Member] \| Sales Revenue, Net [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	7.00%	9.00%	8.00%	10.00%
Provision for Uncollectibles [Member] \| Sales Revenue, Net [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	29.00%	18.00%	25.00%	20.00%

Contracts and Other Revenue

No definition available.

Name:	amsg_ContractsandOtherRevenue
Namespace Prefix:	amsg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percent healthcare revenues governmental programs.

+ References

No definition available.

+ Details

Name:	amsg_PercentHealthcareRevenuesGovernmentalPrograms
Namespace Prefix:	amsg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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=51801978&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=49121117&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=51801978&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=49121117&loc=d3e13537-108611

+ Details

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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

Name:	us-gaap_EntityWideRevenueMajorCustomerLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of revenue recognized for providing services to patients, net of provisions for contractual allowances and discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 605
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=51673510&loc=d3e8184-115640

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 605
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=51673510&loc=d3e8195-115640

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 605
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=51673510&loc=SL9156442-115640

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 605
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51673531&loc=SL9156464-115641

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 605
-Section 45
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51673510&loc=SL9156442-115640

+ Details

Name:	us-gaap_HealthCareOrganizationPatientServiceRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.5)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

+ Details

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

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

+ Details

Name:	us-gaap_Revenues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=amsg_AmbulatoryServicesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=amsg_PhysicianServicesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_HealthCareOrganizationRevenueSourcesAxis=amsg_MedicareMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_HealthCareOrganizationRevenueSourcesAxis=amsg_MedicaidMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_HealthCareOrganizationRevenueSourcesAxis=us-gaap_ThirdPartyPayorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_HealthCareOrganizationRevenueSourcesAxis=us-gaap_SelfPayMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueNetMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ProductOrServiceAxis=amsg_HealthCareOrganizationPatientServiceRevenueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ProductOrServiceAxis=amsg_ContractandOtherRevenueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ProductOrServiceAxis=amsg_ProvisionforUncollectiblesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: