Other Borrowed Funds (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2013	Dec. 31, 2012
Other Borrowed Funds
Other borrowed funds	$ 1,289,493	$ 749,027
Percentage of increase in other borrowed funds	72.20%

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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