Accumulated other comprehensive income (loss) (Tables)  | 
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| Accumulated other comprehensive income (loss) {2} | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Accumulated other comprehensive income (loss) | 
 The changes in the balances for accumulated other comprehensive income (loss) (AOCI) for the periods ended September 30, 2016 and 2015 were as follows: 
 
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- References No definition available. 
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- Definition Tabular disclosure of components of comprehensive income (loss). Includes, but is not limited to, foreign currency translation adjustments, foreign currency transactions designated as economic hedges of a net investment in foreign entity, gain (loss) and prior service cost (credit) for pension plans and other postretirement benefit plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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