Consolidated Statements of Cash Flows - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015
Cash Flows from Operating Activities:
Net income		$ 381,668	$ 357,651
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for (recoveries of) loan losses		664	(8,687)
Depreciation and amortization		24,603	23,339
Amortization of discounts and premiums, net		(25,114)	(5,157)
Amortization of core deposit intangibles		1,994	4,209
Net gain on sales of securities		(413)	(943)
Net gain on sales of loans		(49,809)	(55,315)
Stock-based compensation		24,611	22,594
Deferred tax expense (benefit)		37,569	(14,068)
Changes in assets and liabilities:
Decrease in other assets		353,403	70,915
(Decrease) increase in other liabilities		(11,608)	11,072
Origination of loans held for sale		(3,579,435)	(3,847,702)
Proceeds from sales of loans originated for sale		3,237,704	3,715,652
Net cash provided by operating activities		395,837	273,560
Cash Flows from Investing Activities:
Proceeds from repayment of securities held to maturity		2,356,766	331,663
Proceeds from repayment of securities available for sale		50,010	8,930
Proceeds from sales of securities held to maturity			19,730
Proceeds from sales of securities available for sale		264,413	256,900
Purchase of securities held to maturity		(10,086)	(20,021)
Purchase of securities available for sale		(271,836)	(256,500)
Redemption of Federal Home Loan Bank stock		463,623	432,909
Purchase of Federal Home Loan Bank stock		(386,007)	(456,055)
Proceeds from sales of loans		1,354,796	1,562,908
Other changes in loans, net		(2,623,161)	(2,211,774)
Purchase of premises and equipment		(69,665)	(31,860)
Net cash provided by (used in) investing activities		1,128,853	(363,170)
Cash Flows from Financing Activities:
Net increase (decrease) in deposits		712,841	(48,563)
Net decrease in short-term borrowed funds		(1,927,800)	(202,300)
Proceeds from long-term borrowed funds		181,000	1,723,500
Repayments of long-term borrowed funds			(1,023,902)
Tax effect of stock plans	[1]		2,355
Cash dividends paid on common stock		(248,081)	(332,837)
Payments relating to treasury shares received for restricted stock award tax payments	[1]	(8,542)	(6,999)
Net cash (used in) provided by financing activities		(1,290,582)	111,254
Net increase in cash and cash equivalents		234,108	21,644
Cash and cash equivalents at beginning of period		537,674	564,150
Cash and cash equivalents at end of period		771,782	585,794
Supplemental information:
Cash paid for interest		283,418	413,029
Cash paid for income taxes		135,192	187,663
Non-cash investing and financing activities:
Transfers to other real estate owned from loans		18,691	40,680
Transfer of loans from held for investment to held for sale		1,339,679	1,541,192
Transfer of loans from held for sale to held for investment			153,578
Shares issued for restricted stock awards		$ 8,985	$ 7,709

[1] See Note 14, "Impact of Recent Accounting Pronouncements" for a discussion of the Company's adoption of ASU No. 2016-09.