Acquisitions (Details 5) (USD $) In Thousands, unless otherwise specified	Jun. 04, 2011
Loans at acquisition date
Acquired Impaired	$ 535,489
Acquired Performing	5,911,353
Total Acquired Loans	6,446,842
Commercial non-real estate [Member]
Loans at acquisition date
Acquired Impaired	128,813
Acquired Performing	2,414,002
Total Acquired Loans	2,542,815
Commercial real estate owner-occupied [Member]
Loans at acquisition date
Acquired Impaired	91,885
Acquired Performing	856,583
Total Acquired Loans	948,468
Construction and land development [Member]
Loans at acquisition date
Acquired Impaired	159,438
Acquired Performing	564,795
Total Acquired Loans	724,233
Commercial real estate non-owner occupied [Member]
Loans at acquisition date
Acquired Impaired	86,573
Acquired Performing	839,258
Total Acquired Loans	925,831
Commercial/real estate [Member]
Loans at acquisition date
Acquired Impaired	466,709
Acquired Performing	4,674,638
Total Acquired Loans	5,141,347
Residential mortgage Loans [Member]
Loans at acquisition date
Acquired Impaired	68,780
Acquired Performing	818,152
Total Acquired Loans	886,932
Consumer loan [Member]
Loans at acquisition date
Acquired Impaired	0
Acquired Performing	418,563
Total Acquired Loans	$ 418,563