Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Assets
Cash and due from banks	$ 512,931		$ 710,739
Interest-bearing cash and cash equivalents	574,282		575,500
Trading securities	91,616		214,102
Investment securities	677,878	[1]	499,534	[2]
Available for sale securities	10,147,162		11,287,221
Fair value option securities	167,125		284,296
Restricted equity securities	85,240		64,807
Residential mortgage loans held for sale	200,546		293,762
Loans	12,792,264		12,311,456
Allowance for loan losses	(185,396)		(215,507)
Loans, net of allowance	12,606,868		12,095,949
Premises and Equipment, net	277,849		265,920
Receivables	117,126		114,185
Goodwill	359,759		361,979
Intangible assets, net	24,564		28,192
Mortgage servicing rights, net	153,333		100,812
Real estate and other repossessed assets	92,272		103,791
Derivative contracts	265,012		338,106
Cash surrender value of bank-owned life insurance	284,801		274,531
Receivable on unsettled securities trades	17,174		211,052
Other assets	359,894		324,153
Total assets	27,015,432		28,148,631
Liabilities and Shareholders' Equity [Abstract]
Noninterest-bearing demand deposits	7,316,277		8,038,286
Interest-bearing deposits:
Transaction	9,934,051		9,888,038
Savings	323,006		284,744
Time	2,695,993		2,967,992
Total deposits	20,269,327		21,179,060
Funds purchased	868,081		1,167,416
Repurchase agreements	813,454		887,030
Other borrowings	1,040,353		651,775
Subordinated debentures	347,802		347,633
Accrued interest, taxes and expense	194,870		176,678
Derivative contracts	247,185		283,589
Due on unsettled securities trades	45,740		297,453
Other liabilities	133,647		164,316
Total liabilities	23,960,459		25,154,950
Shareholders' equity:
Common stock	4		4
Capital surplus	898,586		859,278
Retained earnings	2,349,428		2,137,541
Treasury stock	(202,346)		(188,883)
Accumulated other comprehensive income (loss)	(25,623)		149,920
Total shareholders' equity	3,020,049		2,957,860
Non-controlling interest	34,924		35,821
Total equity	3,054,973		2,993,681
Total liabilities and equity	$ 27,015,432		$ 28,148,631

[1] Carrying value includes $1.8 million of net unrealized gain which remains in Accumulated other comprehensive income (“AOCI”) in the Consolidated Balance Sheets related to certain securities transferred from the Available for Sale securities portfolio to the Investment securities portfolio as discussed in greater detail following.

[2] Carrying value includes $5.0 million of net unrealized gain which remains in AOCI in the Consolidated Balance Sheets related to certain securities transferred from the Available for Sale securities portfolio to the Investment securities portfolio as discussed in greater detail following.