Statements of Cash Flows (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012
Statements of Cash Flows [Abstract]
Income taxes paid	$ 14,220		$ 37,551
Interest expense paid on deposits and borrowings	18,656		24,197
Noncash transfers from loans to foreclosed properties	34,226	[1]	33,740	[1]
Assets acquired in business combination	1,845,930		234,960
Liabilities assumed in business combination	$ 1,821,066		$ 209,322

[1] Includes transfers from covered loans to foreclosed properties