Contingencies and Litigation - Other Contingencies (Details) loans in Millions, $ in Millions	6 Months Ended
Jun. 30, 2017 USD ($) loans
Surety Bond [Member]
Guarantor Obligations [Line Items]
Maximum exposure, undiscounted	$ 645
Letter of Credit [Member]
Guarantor Obligations [Line Items]
Maximum exposure, undiscounted	$ 128
Federal Family Education Loan Program (FFEL) Guaranteed Loans [Member]
Guarantor Obligations [Line Items]
Outstanding Student Loan Portfolio, Loans \| loans	1.1
Outstanding Principal Balance - Student Loan Portfolio	$ 18,300
Reserves for losses on defaulted loans	$ 2
State Of Texas v. Xerox Corporation, Xerox State Healthcare, LLC, and ACS State Healthcare, LLC
Guarantor Obligations [Line Items]
Loss Contingency, Damages Sought, Multiplier Of Overpayment Amounts	2

Loss Contingency, Damages Sought, Multiplier of Overpayment Amounts

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- Definition

Outstanding Student Loan Portfolio, Loans

+ References

No definition available.

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- Definition

Reserves for losses on defaulted student loans

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248

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- Definition

This is the result of the principal amount outstanding of total loans managed or securitized less securitized loans and loans that are in the process of being securitized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82924980&loc=d3e107314-111719

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