XML 34 R35.htm IDEA: XBRL DOCUMENT v2.4.1.9
Cash dividends (Details) (USD $)
 6 Months Ended
Apr. 04, 2015
Sep. 30, 2014
Preference share dividends [Abstract]    
Series A Convertible Preferred Stock, stated value (in dollars per share) $ 0.10us-gaap_PreferredStockParOrStatedValuePerShare $ 0.10us-gaap_PreferredStockParOrStatedValuePerShare
Series A Convertible Preferred Stock [Member]    
Preference share dividends [Abstract]    
Maximum shares to be issued (in shares) 460,769sev_MaximumAnnualDividendShares
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember		  
Series A Convertible Preferred Stock, stated value (in dollars per share) $ 24us-gaap_PreferredStockParOrStatedValuePerShare
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember		  
Percentage of cumulative annual dividend, Series A Convertible Preferred Stock (in hundredths) 4.00%us-gaap_PreferredStockDividendRatePercentage
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember		  
Semi annual dividend $ 221,169sev_SemiAnnualDividendDeclared
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember		  
Dividend payable Apr. 15, 2015  
Next semi-annual dividend payable Oct. 15, 2015