Deferred costs and other intangibles (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Acquired Indefinite-lived Intangible Assets
Deferred leasing costs	$ 12,108us-gaap_DeferredCostsLeasingGross	$ 18,307us-gaap_DeferredCostsLeasingGross
Deferred financing costs	66,424us-gaap_DeferredFinanceCostsGross	53,013us-gaap_DeferredFinanceCostsGross
Intangible assets:
Intangible assets	87,456	86,988
Less: accumulated amortization	(22,189)	(32,406)
Total	65,267amh_DeferredCostsAndIntangibleAssetsNet	54,582amh_DeferredCostsAndIntangibleAssetsNet
Value of In-place Leases
Intangible assets:
Intangible assets	3,724	10,468
Trademark
Intangible assets:
Intangible assets	3,100	3,100
Database
Intangible assets:
Intangible assets	$ 2,100	$ 2,100

Accumulated amount of amortization of deferred costs and finite-lived intangible assets.

No definition available.

Name:	amh_DeferredCostsAndIntangibleAssetsAccumulatedAmortization
Namespace Prefix:	amh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before amortization of the sum of deferred costs and finite lived intangible assets.

+ References

No definition available.

+ Details

Name:	amh_DeferredCostsAndIntangibleAssetsGross
Namespace Prefix:	amh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Aggregate carrying amount of deferred costs and intangible assets, net of accumulated amortization.

+ References

No definition available.

+ Details

Name:	amh_DeferredCostsAndIntangibleAssetsNet
Namespace Prefix:	amh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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

- Definition

For an unclassified balance sheet, this element represents costs incurred by the lessor that are (a) costs to originate a lease incurred in transactions with independent third parties that (i) result directly from and are essential to acquire that lease and (ii) would not have been incurred had that leasing transaction not occurred and (b) certain costs directly related to specified activities performed by the lessor for that lease. Those activities are: evaluating the prospective lessee's financial condition; evaluating and recording guarantees, collateral, and other security arrangements; negotiating lease terms; preparing and processing lease documents; and closing the transaction. This amount is before considering accumulated amortization representing the periodic charge to earnings to recognize the deferred costs over the term of the related lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 25

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=6748888&loc=d3e40246-112709

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 25

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=6748888&loc=d3e40588-112709

+ Details

Name:	us-gaap_DeferredCostsLeasingGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For an unclassified balance sheet, the amount as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain. Such amount is before the consideration of accumulated amortization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28555-108399

+ Details

Name:	us-gaap_DeferredFinanceCostsGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_DatabasesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_LeasesAcquiredInPlaceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_TrademarksMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: