Consolidated Statement of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities
Net income	$ 298,528	$ 241,613
Adjustments to reconcile net income to net cash provided by operating activities
Provision for credit losses	49,000	38,000
Depreciation and amortization of premises and equipment	27,141	24,178
Amortization of capitalized servicing rights	12,249	12,199
Amortization of core deposit and other intangible assets	12,319	6,793
Provision for deferred income taxes	50,075	37,052
Asset write-downs	8,940	2,379
Net gain on sales of assets	(5,399)	(1,066)
Net change in accrued interest receivable, payable	(16,530)	(2,200)
Net change in other accrued income and expense	70,766	(80,084)
Net change in loans originated for sale	211	197,708
Net change in trading account assets and liabilities	(59,080)	(18,206)
Net cash provided by operating activities	448,220	458,366
Cash flows from investing activities
Proceeds from sales of investment securities Available for sale	518	693
Proceeds from sales of investment securities Other	18,121	132
Proceeds from maturities of investment securities Available for sale	511,549	369,649
Proceeds from maturities of investment securities Held to maturity	132,636	148,708
Purchases of investment securities Available for sale	(311,302)	(1,871,491)
Purchases of investment securities Held to maturity	(5,343)	(7,442)
Purchases of investment securities Other	(124)	(348)
Net increase in loans and leases	(439,712)	(666,220)
Net (increase) decrease in interest-bearing deposits at banks	(1,950,831)	179,376
Capital expenditures, net	(16,307)	(9,598)
Net decrease in loan servicing advances	37,600	76,145
Other, net	7,920	(21,940)
Net cash used by investing activities	(2,015,275)	(1,802,336)
Cash flows from financing activities
Net increase (decrease) in deposits	2,264,623	(4,543)
Net increase (decrease) in short-term borrowings	(343,838)	819
Proceeds from long-term borrowings		1,500,000
Payments on long-term borrowings	(317,187)	(1,797)
Purchases of treasury stock	(100,000)
Dividends paid - common	(112,000)	(93,631)
Dividends paid - preferred	(17,368)	(17,368)
Other, net	2,960	(46,014)
Net cash provided by financing activities	1,377,190	1,337,466
Net decrease in cash and cash equivalents	(189,865)	(6,504)
Cash and cash equivalents at beginning of period	1,368,040	1,373,357
Cash and cash equivalents at end of period	1,178,175	1,366,853
Supplemental disclosure of cash flow information
Interest received during the period	968,223	726,475
Interest paid during the period	146,568	75,776
Income taxes paid (refunded) during the period	(86,146)	88,578
Supplemental schedule of noncash investing and financing activities
Real estate acquired in settlement of loans	33,737	10,846
Securitization of residential mortgage loans allocated to Available-for-sale investment securities	8,452	12,920
Securitization of residential mortgage loans allocated to capitalized servicing rights	$ 92	$ 143