CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME Unaudited (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Comprehensive Income
Net income (loss)	$ 361us-gaap_ProfitLoss	$ 319us-gaap_ProfitLoss
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Unrealized holding gains (losses) on available-for-sale securities arising during period	141	113
Reclassification adjustment for net (gains) losses included in net income	(8)	(3)
Unrealized holding gains (losses) on cash flow hedge derivatives arising during period	34	10
Reclassification adjustment for net gains on cash flow hedge derivatives included in net income	(10)	(7)
Reclassification of amounts to net periodic benefit costs	2	1
Other comprehensive income (loss)	159	114
Comprehensive income	520	433
Comprehensive income attributable to noncontrolling interests		1
Comprehensive income attributable to Bancorp	$ 520us-gaap_ComprehensiveIncomeNetOfTax	$ 432us-gaap_ComprehensiveIncomeNetOfTax

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount after tax of reclassification adjustment from accumulated other comprehensive (income) loss related to net period benefit cost (credit) for pension and other postretirement defined benefit plans.

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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