Comprehensive income (Details 1) (USD $) In Thousands	9 Months Ended			9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Investment securities with OTTI [Member]	Sep. 30, 2010 Investment securities with OTTI [Member]	Sep. 30, 2011 Investment securities all other [Member]	Sep. 30, 2010 Investment securities all other [Member]	Sep. 30, 2011 Cash flow hedges [Member]	Sep. 30, 2010 Cash flow hedges [Member]	Sep. 30, 2011 Foreign currency translation adjustment [Member]	Sep. 30, 2010 Foreign currency translation adjustment [Member]	Dec. 31, 2009 Foreign currency translation adjustment [Member]	Sep. 30, 2011 Defined benefit plans [Member]	Sep. 30, 2010 Defined benefit plans [Member]
Accumulated other comprehensive income (loss), net consisted of unrealized gains (losses)
Beginning Balance	$ (205,220)	$ (335,997)	$ (87,053)	$ (76,772)	$ 2,332	$ (142,853)	$ 393	$ 674	$ 0	$ 0	$ 0	$ (120,892)	$ (117,046)
Net gain (loss) during period	12,687	143,443	3,016	(5,022)	3,954	145,414	(211)	(211)	(503)			6,431	3,262
Ending Balance	$ (192,533)	$ (192,554)	$ (84,037)	$ (81,794)	$ 6,286	$ 2,561	$ 182	$ 463	$ (503)	$ 0	$ 0	$ (114,461)	$ (113,784)

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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

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-Name FASB Staff Position (FSP)

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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+ Details

- Definition

This element represents Other Comprehensive Income or Loss, Net of Tax, for the period attributable to the parent entity. Includes deferred gains or losses on qualifying hedges, unrealized holding gains or losses on available-for-sale securities, minimum pension liability, and cumulative translation adjustment.

+ References

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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+ Details