Loans and Loans Held for Sale - Summary of Changes in Loans Held for Sale (Detail) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Loans Receivables [Abstract]
Balance at beginning of the period	$ 684	$ 916	$ 1,649
New originations	1,539	1,655	1,650
Transfers from (to) held to maturity, net	22	22	6
Loan sales	(1,802)	(1,943)	(2,466)
Loan draws (payments), net	(1)	(11)	(4)
Balance at end of period	$ 442	$ 639	$ 835

Loans receivable held for sale reconciliation to cash flow loan draws payments.

No definition available.

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- Definition

Loans receivable held for sale reconciliation to cash flow transfers from to held to maturity net.

+ References

No definition available.

+ Details

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- Definition

Loans Receivables [Abstract]

+ References

No definition available.

+ Details

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- Definition

Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

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- Definition

Amount, after allowance for bad debt, of additions to loan receivables held-for-sale that are not part of a disposal group.

+ References

+ Details

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- Definition

Amount, after allowance for bad debt, of deductions to loan receivables held-for-sale that are not part of a disposal group.

+ References

+ Details

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