Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity (Details)

v2.4.1.9
Stockholders' Equity (Details) (USD $)
 3 Months Ended
Dec. 31, 2013
Dec. 31, 2014
Dec. 31, 2010
Class of Stock [Line Items]      
Common stock, par value (in dollars per share)     $ 0.0001us-gaap_CommonStockParOrStatedValuePerShare
Preferred stock, shares authorized (in shares) 5,000,000us-gaap_PreferredStockSharesAuthorized 5,000,000us-gaap_PreferredStockSharesAuthorized  
Preferred stock, par value (in dollars per share) $ 0.0001us-gaap_PreferredStockParOrStatedValuePerShare $ 0.0001us-gaap_PreferredStockParOrStatedValuePerShare  
Class A Common Stock      
Class of Stock [Line Items]      
Common stock, shares authorized (in shares) 500,000,000us-gaap_CommonStockSharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassAMember 		500,000,000us-gaap_CommonStockSharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassAMember 		 
Common stock, par value (in dollars per share) $ 0.0001us-gaap_CommonStockParOrStatedValuePerShare
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassAMember 		$ 0.0001us-gaap_CommonStockParOrStatedValuePerShare
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassAMember 		 
Number of Votes Per Share   1amrc_NumberofVotesPerShare
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassAMember 		 
Shares retired during the year (in shares) 4,833,284us-gaap_StockRepurchasedAndRetiredDuringPeriodShares
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassAMember 		   
Class B Common Stock      
Class of Stock [Line Items]      
Common stock, shares authorized (in shares) 144,000,000us-gaap_CommonStockSharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassBMember 		144,000,000us-gaap_CommonStockSharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassBMember 		 
Common stock, par value (in dollars per share) $ 0.0001us-gaap_CommonStockParOrStatedValuePerShare
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassBMember 		$ 0.0001us-gaap_CommonStockParOrStatedValuePerShare
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassBMember 		 
Number of Votes Per Share   5amrc_NumberofVotesPerShare
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassBMember 		 
Preferred Stock      
Class of Stock [Line Items]      
Preferred stock, shares authorized (in shares)   5,000,000us-gaap_PreferredStockSharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= us-gaap_PreferredStockMember 		 
Preferred stock, par value (in dollars per share)   $ 0.0001us-gaap_PreferredStockParOrStatedValuePerShare
/ us-gaap_StatementClassOfStockAxis
= us-gaap_PreferredStockMember