Consolidated Balance Sheets - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016
ASSETS
Cash and due from banks		$ 332,601	$ 446,558
Interest-bearing deposits in other financial institutions		337,167	149,175
Federal funds sold and securities purchased under agreements to resell		19,700	46,500
Investment securities held to maturity, at amortized cost		1,554,843	1,273,536
Investment securities available for sale, at fair value		4,300,490	4,680,226
Federal Home Loan Bank and Federal Reserve Bank stocks, at cost		139,273	140,001
Residential loans held for sale		34,051	108,010
Commercial loans held for sale		2,901	12,474
Loans		20,147,683	20,054,716
Allowance for loan losses		(282,672)	(278,335)
Loans, net		19,865,011	19,776,381
Premises and equipment, net		332,884	330,315
Goodwill		972,006	971,951
Mortgage servicing rights		60,702	61,476
Other intangible assets		15,026	15,377
Trading assets		49,306	52,398
Other assets	[1]	1,093,896	1,074,937
Total assets		29,109,857	29,139,315
LIABILITIES AND STOCKHOLDERS’ EQUITY
Noninterest-bearing demand deposits		5,338,212	5,392,208
Interest-bearing deposits		16,489,823	16,496,240
Total deposits		21,828,035	21,888,448
Federal funds purchased and securities sold under agreements to repurchase		650,188	508,347
Other short-term funding		430,679	583,688
Long-term funding	[1]	2,761,955	2,761,795
Trading liabilities		47,561	51,103
Accrued expenses and other liabilities		246,645	254,622
Total liabilities		25,965,063	26,048,003
Stockholders’ equity
Preferred equity		159,929	159,929
Common stock		1,630	1,630
Surplus		1,469,744	1,459,498
Retained earnings		1,709,514	1,695,764
Accumulated other comprehensive loss		(56,344)	(54,679)
Treasury stock, at cost		(139,679)	(170,830)
Total common equity		2,984,865	2,931,383
Total stockholders’ equity		3,144,794	3,091,312
Total liabilities and stockholders’ equity		$ 29,109,857	$ 29,139,315
Preferred shares issued (in shares)		165,000	165,000
Preferred shares authorized (par value $1.00 per share) (in shares)		750,000	750,000
Common shares issued (in shares)		163,030,209	163,030,209
Common shares authorized (par value $0.01 per share) (in shares)		250,000,000	250,000,000
Treasury shares of common stock (in shares)		9,296,566	10,909,362

[1] (1)Effective January 1, 2017, residential loans originated for sale are accounted for under the fair value option. Prior periods have not been restated. For more information on this accounting policy change, please refer to Note 3 to the Notes to the Consolidated Financial Statements.