Contingent Liabilities and Commitments with Off Balance Sheet Risk (Details 1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Summary of minimum future contractual obligation under renewal of contract
2012	$ 13,464
2013	11,016
2014	8,568
2015	6,120
2016	$ 3,672

Amount of contractual obligation maturing in the fifth fiscal year following the latest fiscal year.

No definition available.

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Period Type:	instant

Amount of contractual obligation maturing in the fourth fiscal year following the latest fiscal year.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of contractual obligation maturing in the next fiscal year following the latest fiscal year.

No definition available.

Name:	us-gaap_ContractualObligationDueInNextTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of contractual obligation maturing in the second fiscal year following the latest fiscal year.

No definition available.

Name:	us-gaap_ContractualObligationDueInSecondYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of contractual obligation maturing in the third fiscal year following the latest fiscal year.

No definition available.

Name:	us-gaap_ContractualObligationDueInThirdYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration