Loans and Allowances for Credit Losses Part 4 (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	$ 319,534		$ 360,258
Impaired loans, recorded investment, total	281,970		294,365
Impaired loans, recorded investment with no related allowance	279,827		283,039
Impaired loans, recorded investment with related allowance	2,143		11,326
Impaired loans, related allowance	954		4,233
Impaired loans, average recorded investment	282,658		341,335
Impaired loans, interest income recognized	8,543		8,308
Commercial Loan [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	30,826		43,230
Impaired loans, recorded investment, total	16,760		24,467
Impaired loans, recorded investment with no related allowance	15,549		23,140
Impaired loans, recorded investment with related allowance	1,211		1,327
Impaired loans, related allowance	573		230
Impaired loans, average recorded investment	20,614		46,640
Impaired loans, interest income recognized	0		0
Energy [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	1,860		2,460
Impaired loans, recorded investment, total	1,860		2,460
Impaired loans, recorded investment with no related allowance	1,860		2,460
Impaired loans, recorded investment with related allowance	0		0
Impaired loans, related allowance	0		0
Impaired loans, average recorded investment	2,160		1,398
Impaired loans, interest income recognized	0		0
Services [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	6,486		15,715
Impaired loans, recorded investment, total	4,922		12,090
Impaired loans, recorded investment with no related allowance	3,791		11,940
Impaired loans, recorded investment with related allowance	1,131		150
Impaired loans, related allowance	516		149
Impaired loans, average recorded investment	8,506		14,529
Impaired loans, interest income recognized	0		0
Wholesale/retail [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	11,009		9,186
Impaired loans, recorded investment, total	6,969		3,077
Impaired loans, recorded investment with no related allowance	6,937		3,016
Impaired loans, recorded investment with related allowance	32		61
Impaired loans, related allowance	9		15
Impaired loans, average recorded investment	5,023		12,129
Impaired loans, interest income recognized	0		0
Manufacturing [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	746		2,447
Impaired loans, recorded investment, total	592		2,007
Impaired loans, recorded investment with no related allowance	592		2,007
Impaired loans, recorded investment with related allowance	0		0
Impaired loans, related allowance	0		0
Impaired loans, average recorded investment	1,300		12,529
Impaired loans, interest income recognized	0		0
Healthcare [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	2,193		4,256
Impaired loans, recorded investment, total	1,586		3,166
Impaired loans, recorded investment with no related allowance	1,538		2,050
Impaired loans, recorded investment with related allowance	48		1,116
Impaired loans, related allowance	48		66
Impaired loans, average recorded investment	2,376		4,326
Impaired loans, interest income recognized	0		0
Integrated food services [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	0		684
Impaired loans, recorded investment, total	0		684
Impaired loans, recorded investment with no related allowance	0		684
Impaired loans, recorded investment with related allowance	0		0
Impaired loans, related allowance	0		0
Impaired loans, average recorded investment	342		342
Impaired loans, interest income recognized	0		0
Other commercial and industrial [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	8,532		8,482
Impaired loans, recorded investment, total	831		983
Impaired loans, recorded investment with no related allowance	831		983
Impaired loans, recorded investment with related allowance	0		0
Impaired loans, related allowance	0		0
Impaired loans, average recorded investment	907		1,387
Impaired loans, interest income recognized	0		0
Commercial Real Estate [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	49,637		86,001
Impaired loans, recorded investment, total	40,850		60,626
Impaired loans, recorded investment with no related allowance	40,328		53,051
Impaired loans, recorded investment with related allowance	522		7,575
Impaired loans, related allowance	133		3,109
Impaired loans, average recorded investment	50,739		79,911
Impaired loans, interest income recognized	0		0
Residential construction and land development [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	20,804		44,721
Impaired loans, recorded investment, total	17,377		26,131
Impaired loans, recorded investment with no related allowance	17,050		25,575
Impaired loans, recorded investment with related allowance	327		556
Impaired loans, related allowance	107		155
Impaired loans, average recorded investment	21,754		44,003
Impaired loans, interest income recognized	0		0
Retail [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	6,133		9,797
Impaired loans, recorded investment, total	4,857		8,117
Impaired loans, recorded investment with no related allowance	4,857		8,117
Impaired loans, recorded investment with related allowance	0		0
Impaired loans, related allowance	0		0
Impaired loans, average recorded investment	6,487		7,490
Impaired loans, interest income recognized	0		0
Office [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	7,848		8,949
Impaired loans, recorded investment, total	6,391		6,829
Impaired loans, recorded investment with no related allowance	6,383		6,604
Impaired loans, recorded investment with related allowance	8		225
Impaired loans, related allowance	8		21
Impaired loans, average recorded investment	6,610		9,143
Impaired loans, interest income recognized	0		0
Multifamily [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	7		3,189
Impaired loans, recorded investment, total	7		2,706
Impaired loans, recorded investment with no related allowance	7		2,706
Impaired loans, recorded investment with related allowance	0		0
Impaired loans, related allowance	0		0
Impaired loans, average recorded investment	1,357		3,110
Impaired loans, interest income recognized	0		0
Industrial [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	252		3,968
Impaired loans, recorded investment, total	252		3,968
Impaired loans, recorded investment with no related allowance	252		0
Impaired loans, recorded investment with related allowance	0		3,968
Impaired loans, related allowance	0		2,290
Impaired loans, average recorded investment	2,110		1,984
Impaired loans, interest income recognized	0		0
Other commercial real estate [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	14,593		15,377
Impaired loans, recorded investment, total	11,966		12,875
Impaired loans, recorded investment with no related allowance	11,779		10,049
Impaired loans, recorded investment with related allowance	187		2,826
Impaired loans, related allowance	18		643
Impaired loans, average recorded investment	12,421		14,181
Impaired loans, interest income recognized	0		0
Residential Mortgage [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	237,843		228,149
Impaired loans, recorded investment, total	223,141		206,563
Impaired loans, recorded investment with no related allowance	222,731		204,264
Impaired loans, recorded investment with related allowance	410		2,299
Impaired loans, related allowance	248		769
Impaired loans, average recorded investment	209,340		211,672
Impaired loans, interest income recognized	8,543		8,308
Permanent Mortgage [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	41,870		51,153
Impaired loans, recorded investment, total	34,279		39,863
Impaired loans, recorded investment with no related allowance	33,869		37,564
Impaired loans, recorded investment with related allowance	410		2,299
Impaired loans, related allowance	248		769
Impaired loans, average recorded investment	37,071		32,614
Impaired loans, interest income recognized	1,582		1,590
Permanent mortgages guaranteed by U.S. government agencies [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	188,436	[1]	170,740	[2]
Impaired loans, recorded investment, total	181,598	[1]	160,444	[2]
Impaired loans, recorded investment with no related allowance	181,598	[1]	160,444	[2]
Impaired loans, recorded investment with related allowance	0	[1]	0	[2]
Impaired loans, related allowance	0	[1]	0	[2]
Impaired loans, average recorded investment	165,509	[1]	173,729	[2]
Impaired loans, interest income recognized	6,961	[1]	6,718	[2]
Home equity
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	7,537		6,256
Impaired loans, recorded investment, total	7,264		6,256
Impaired loans, recorded investment with no related allowance	7,264		6,256
Impaired loans, recorded investment with related allowance	0		0
Impaired loans, related allowance	0		0
Impaired loans, average recorded investment	6,760		5,329
Impaired loans, interest income recognized	0		0
Consumer Loan [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	1,228		2,878
Impaired loans, recorded investment, total	1,219		2,709
Impaired loans, recorded investment with no related allowance	1,219		2,584
Impaired loans, recorded investment with related allowance	0		125
Impaired loans, related allowance	0		125
Impaired loans, average recorded investment	1,965		3,112
Impaired loans, interest income recognized	0		0
Indirect automobile [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	719		1,578
Impaired loans, recorded investment, total	717		1,578
Impaired loans, recorded investment with no related allowance	717		1,578
Impaired loans, recorded investment with related allowance	0		0
Impaired loans, related allowance	0		0
Impaired loans, average recorded investment	1,148		1,886
Impaired loans, interest income recognized	0		0
Other consumer [Member]
Impaired loans [Abstract]
Impaired loans, unpaid principal balance	509		1,300
Impaired loans, recorded investment, total	502		1,131
Impaired loans, recorded investment with no related allowance	502		1,006
Impaired loans, recorded investment with related allowance	0		125
Impaired loans, related allowance	0		125
Impaired loans, average recorded investment	817		1,226
Impaired loans, interest income recognized	$ 0		$ 0

[1] 1 All permanent mortgage loans guaranteed by U.S. government agencies are considered impaired as we do not expect full collection of contractual principal and interest. At December 31, 2013, $777 thousand of these loans are nonaccruing and $181 million are accruing based on the guarantee by U.S. government agencies.

[2] 1 All permanent mortgage loans guaranteed by U.S. government agencies are considered impaired as we do not expect full collection of contractual principal and interest. At December 31, 2012, $489 thousand of these loans are nonaccruing and $160 million are accruing based on the guarantee by U.S. government agencies.