Loans and Allowance for Credit Losses Total Impaired Loans by Class Segments (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	$ 127,922	$ 156,599
Unpaid principal balance, with related allowance	212,050	256,798
Unpaid Principal Balance	339,972	413,397
Recorded investment, with no related allowance	94,156	109,938
Recorded investment, with related allowance	177,027	203,451
Recorded Investment	271,183	313,389
Related Allowance	82,040	96,577
Real-estate commercial mortage [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	44,225	54,445
Unpaid principal balance, with related allowance	78,258	100,529
Recorded investment, with no related allowance	33,917	46,768
Recorded investment, with related allowance	59,222	79,566
Related Allowance	25,280	36,060
Commercial - Secured [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	38,023	35,529
Unpaid principal balance, with related allowance	60,556	61,970
Recorded investment, with no related allowance	30,067	28,440
Recorded investment, with related allowance	44,445	47,652
Related Allowance	21,816	26,248
Commercial - unsecured [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	105	0
Unpaid principal balance, with related allowance	2,725	3,139
Recorded investment, with no related allowance	105	0
Recorded investment, with related allowance	2,505	2,789
Related Allowance	1,889	2,177
Real-estate - home equity [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	581	199
Unpaid principal balance, with related allowance	8,322	5,294
Recorded investment, with no related allowance	581	199
Recorded investment, with related allowance	8,322	5,294
Related Allowance	5,316	3,076
Real-estate - residential mortgage [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	1,980	0
Unpaid principal balance, with related allowance	35,554	39,918
Recorded investment, with no related allowance	1,980	0
Recorded investment, with related allowance	46,838	39,918
Related Allowance	20,550	16,295
Construction - commercial residential [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	39,490	62,822
Unpaid principal balance, with related allowance	23,233	41,176
Recorded investment, with no related allowance	24,560	31,233
Recorded investment, with related allowance	12,536	25,632
Related Allowance	5,368	11,287
Construction - Commercial [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	3,518	3,604
Unpaid principal balance, with related allowance	2,302	3,221
Recorded investment, with no related allowance	2,946	3,298
Recorded investment, with related allowance	2,059	1,049
Related Allowance	1,169	506
Construction other [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	1,072	1,127
Recorded investment, with related allowance	1,072	1,127
Related Allowance	634	663
Consumer - direct [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	7	368
Recorded investment, with related allowance	7	368
Related Allowance	5	228
Leasing and other and overdrafts [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	21	56
Recorded investment, with related allowance	21	56
Related Allowance	$ 13	$ 37