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Fair value measurements Level 3 Transfers (Policies) | 9 Months Ended
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Sep. 30, 2013
Fair Value Level 3 Transfer Disclosure [Abstract] |
Fair Value Transfer, Policy [Policy Text Block] | It is our policy to recognize transfers into and transfers out of Level 3 as of the actual date of the event or change in circumstances that caused the transfer.

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- Definition Disclosure of accounting policy for determining when transfers between levels are recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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