Balance Sheets - Parent Company Only (Details) - USD ($) $ in Millions		Dec. 31, 2018	Dec. 31, 2017		Dec. 31, 2016	Dec. 31, 2015
Assets [Abstract]
Cash and Due from Banks		$ 5,791	$ 5,349
Interest-bearing Deposits in Banks and Other Financial Institutions		25	25
Cash and cash equivalents		7,495	6,912		$ 6,423	$ 5,599
Debt Securities, Trading, and Equity Securities, FV-NI	[1]	5,506	5,093
Available-for-sale Securities	[2],[3]	31,442	30,947	[4]
Goodwill		6,331	6,331		6,337
Other Assets	[2],[5]	8,991	9,099
Total assets		215,543	205,962
Liabilities and Shareholders' Equity
Long-term Debt	[6],[7]	15,072	9,785
Other Liabilities		3,226	4,179
Total liabilities		191,263	180,808
Preferred Stock, Value, Outstanding		2,025	2,475		1,225
Common Stock, Value, Outstanding		553	550
Additional Paid in Capital		9,022	9,000
Retained Earnings (Accumulated Deficit)		19,522	17,540
Treasury Stock, Value	[8]	(5,422)	(3,591)
Accumulated Other Comprehensive Income (Loss), Net of Tax		(1,420)	(820)		(821)	(460)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		24,280	25,154		23,618	23,437
Liabilities and Equity		215,543	205,962
Parent Company [Member]
Assets [Abstract]
Cash and Due from Banks		599	701
Interest-bearing Deposits Held at SunTrust		913	2,144
Interest-bearing Deposits in Banks and Other Financial Institutions		24	24
Cash and cash equivalents		1,536	2,869		$ 1,684	$ 2,615
Debt Securities, Trading, and Equity Securities, FV-NI		12	0
Available-for-sale Securities		98	123
Due from Affiliates		1,261	1,218
Equity Method Investments		24,630	24,590
Investments in and Advances to Affiliates, Amount of Equity		1,457	1,423
Goodwill		211	211
Other Assets		686	547
Total assets		29,891	30,981
Liabilities and Shareholders' Equity
Due to Affiliate, Current		5	205
Short-term Bank Loans and Notes Payable		354	350
Long-term Debt		4,536	4,466
Other Liabilities		819	909
Total liabilities		5,714	5,930
Preferred Stock, Value, Outstanding		2,025	2,475
Common Stock, Value, Outstanding		553	550
Additional Paid in Capital		9,022	9,000
Retained Earnings (Accumulated Deficit)		19,522	17,540
Treasury Stock, Value		(5,525)	(3,694)
Accumulated Other Comprehensive Income (Loss), Net of Tax		(1,420)	(820)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		24,177	25,051
Liabilities and Equity		$ 29,891	$ 30,981

[1] Includes trading securities pledged as collateral where counterparties have the right to sell or repledge the collateral of $1,442 million and $1,086 million at December?31, 2018 and December?31, 2017, respectively.

[2] Beginning January 1, 2018, the Company reclassified equity securities previously presented in Securities available for sale to Other assets. Reclassifications have been made to previously reported amounts for comparability.

[3] Includes securities AFS pledged as collateral where counterparties have the right to sell or repledge the collateral of $222 million and $223 million at December?31, 2018 and December?31, 2017, respectively.

[4] Beginning January 1, 2018, the Company reclassified equity securities previously presented in Securities AFS to Other assets on the Consolidated Balance Sheets. Prior periods have been revised to conform to the current presentation for comparability. See Note 11, "Other Assets," for additional information.

[5] Beginning October 1, 2018, the Company reclassified software and related accumulated amortization previously presented in Other assets to Premises, property, and equipment, net. Reclassifications have been made to previously reported amounts for comparability.

[6] Includes $289 million and $530 million of long-term debt measured at fair value at December 31, 2018 and 2017, respectively.

[7] Includes debt of consolidated VIEs of $161 million and $189 million at December?31, 2018 and December?31, 2017, respectively.

[8] Includes noncontrolling interest of $103 million and $103 million at December?31, 2018 and December?31, 2017, respectively.