Securities Available for Sale (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 21,162		$ 25,170
Unrealized Gains	3,276		2,989
Unrealized Losses	29		42
Fair Value	24,409		28,117
US Treasury Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	214		671
Unrealized Gains	10		23
Unrealized Losses	0		0
Fair Value	224		694
US Government Agencies Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,698		1,843
Unrealized Gains	85		89
Unrealized Losses	0		0
Fair Value	1,783		1,932
US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	359		437
Unrealized Gains	19		21
Unrealized Losses	6		4
Fair Value	372		454
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	17,308		20,480
Unrealized Gains	803		743
Unrealized Losses	1		0
Fair Value	18,110		21,223
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	225		252
Unrealized Gains	0		0
Unrealized Losses	17		31
Fair Value	208		221
Collateralized Debt Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost			50
Unrealized Gains			0
Unrealized Losses			0
Fair Value			50
Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	344		460
Unrealized Gains	9		11
Unrealized Losses	5		7
Fair Value	348		464
Corporate And Other Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	42		49
Unrealized Gains	3		2
Unrealized Losses	0		0
Fair Value	45		51
Equity Securities, Coca Cola
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	0		0
Unrealized Gains	2,346		2,099
Unrealized Losses	0		0
Fair Value	2,346		2,099
Equity Securities, Other [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	972	[1]	928	[1]
Unrealized Gains	1	[1]	1	[1]
Unrealized Losses	0	[1]	0	[1]
Fair Value	973	[1]	929	[1]
Equity Securities, Other [Member]
Schedule of Available-for-sale Securities [Line Items]
Federal Reserve Bank Stock	$ 401		$ 398

[1] At June 30, 2012, other equity securities included the following securities at cost: $455 million in FHLB of Atlanta stock, $401 million in Federal Reserve Bank stock, and $116 million in mutual fund investments. At December 31, 2011, other equity securities included the following securities at cost: $342 million in FHLB of Atlanta stock, $398 million in Federal Reserve Bank stock, and $187 million in mutual fund investments.