Condensed Balance Sheet - Parent Company Only (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
Investments in subsidiaries:
Goodwill	$ 2,416		$ 2,416		$ 2,416
Other assets	8,241	[1]	8,358	[1]
Total Assets	138,706		130,443		121,894
Liabilities
Other short-term borrowings	1,556		1,380
Accrued expenses and other liabilities	2,642	[1]	3,487	[1]
Long-term debt (external)	14,967	[1]	9,633	[1]
Total liabilities	123,041		115,817
Shareholders' Equity
Common stock	2,051	[2]	2,051	[2]
Preferred stock	1,331	[3]	1,034	[3]
Capital surplus	2,646		2,561
Retained earnings	11,141		10,156
Accumulated other comprehensive income	429		82		375	470
Treasury stock	(1,972)	[2]	(1,295)	[2]
Noncontrolling interests	39		37
Total Equity	15,626		14,589
Total Liabilities and Equity	138,706		130,443
Parent Company Only
Assets
Short-term Investments	3,189		2,505
Loans to subsidiaries:
Nonbank subsidiaries	984		974
Total loans to subsidiaries	984		974
Investments in subsidiaries:
Nonbank subsidiaries	17,186		16,254
Total investment in subsidiaries	17,186		16,254
Goodwill	80		80
Other assets	451		323
Total Assets	21,890		20,136
Liabilities
Other short-term borrowings	426		311
Accrued expenses and other liabilities	405		442
Long-term debt (external)	5,394		4,757
Total liabilities	6,225		5,510
Shareholders' Equity
Common stock	2,051		2,051
Preferred stock	1,331		1,034
Capital surplus	2,646		2,561
Retained earnings	11,141		10,156
Accumulated other comprehensive income	429		82
Treasury stock	(1,972)		(1,295)
Noncontrolling interests	39		37
Total Equity	15,665		14,626
Total Liabilities and Equity	$ 21,890		$ 20,136

[1] At December 31, 2014 and 2013, includes $179 and $49 of cash and due from banks, $47 and $48 of commercial mortgage loans, $3,331 and $1,010 of automobile loans, $(22) and $(15) of ALLL, $25 and $13 of other assets, $5 and $1 of other liabilities, $3,434 and $1,048 of long-term debt from consolidated VIEs that are included in their respective captions. For further information, refer to Note 10.

[2] Common shares: Stated value $2.22 per share; authorized 2,000,000; outstanding at December 31, 2014 – 824,046,952 (excludes 99,845,629 treasury shares) and December 31, 2013 – 855,305,745 (excludes 68,586,836 treasury shares).

[3] 446,000 and 458,000 shares of undesignated no par value preferred stock are authorized and unissued at December 31, 2014 and December 31, 2013, respectively; fixed-to-floating rate non-cumulative Series H perpetual preferred stock with a $25,000 liquidation preference: 24,000 authorized, issued and outstanding at December 31, 2014 and December 31, 2013; fixed-to-floating rate non-cumulative Series I perpetual preferred stock with a $25,000 liquidation preference: 18,000 authorized, issued and outstanding at December 31, 2014 and December 31, 2013; and fixed-to-floating rate non-cumulative Series J perpetual preferred stock with a $25,000 liquidation preference: 12,000 authorized shares, issues and outstanding at December 31, 2014.