FDIC Indemnification Asset (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011
Fdic Indemnification Asset Details
Receivable related to claims submitted, not yet received	$ 20,722	$ 13,377	$ 13,802
Receivable related to estimated future claims on loans	71,542	90,275	90,258
Receivable related to estimated future claims on other real estate owned	15,351	18,025	16,890
FDIC indemnification asset	$ 107,615	$ 121,677	$ 120,950

Carrying amount of receivable assets originating from the indemnification agreement with the Federal Deposit Insurance Corporation (FDIC), in which the FDIC is to partially cover losses.

No definition available.

Name:	us-gaap_FDICIndemnificationAsset
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant