RENTAL EXPENSE AND LEASE COMMITMENTS - Commitments (Details) $ in Millions	Dec. 31, 2016 USD ($)
Operating lease commitments
Gross minimum rental commitments (including vacant space below) for 2017	$ 1,414
Gross minimum rental commitments (including vacant space below) for 2018	1,328
Gross minimum rental commitments (including vacant space below) for 2019	1,218
Gross minimum rental commitments (including vacant space below) for 2020	1,016
Gross minimum rental commitments (including vacant space below) for 2021	796
Gross minimum rental commitments (including vacant space below) beyond 2021	1,111
Vacant space for 2017	42
Vacant space for 2018	29
Vacant space for 2019	20
Vacant space for 2020	15
Vacant space for 2021	11
Vacant space beyond 2021	9
Sublease income commitments for 2017	12
Sublease income commitments for 2018	8
Sublease income commitments for 2019	6
Sublease income commitments for 2020	3
Capital lease commitments
Capital lease commitments for 2017	1
Capital lease commitments for 2018	2
Capital lease commitments for 2019	2
Capital lease commitments for 2020	$ 2

Amount of future rental payments receivable on noncancelable subleasing arrangements due within one year.

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- Definition

Amount of future rental payments receivable on noncancelable subleasing arrangements due within four years.

+ References

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- Definition

Amount of future rental payments receivable on noncancelable subleasing arrangements due within three years.

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Amount of future rental payments receivable on noncancelable subleasing arrangements due within two years.

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- Definition

Vacant space, associated with infrastructure reductions and restructuring actions, rental payments within one year of the balance sheet date relating to leases defined as operating.

+ References

No definition available.

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- Definition

Vacant space, associated with infrastructure reductions and restructuring actions, rental payments within the fifth year of the balance sheet date relating to leases defined as operating.

+ References

No definition available.

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Vacant space, associated with infrastructure reductions and restructuring actions, rental payments within the fourth year of the balance sheet date relating to leases defined as operating.

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No definition available.

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Vacant space, associated with infrastructure reductions and restructuring actions, rental payments within the third year of the balance sheet date relating to leases defined as operating.

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No definition available.

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Vacant space, associated with infrastructure reductions and restructuring actions, rental payments within the second year of the balance sheet date relating to leases defined as operating.

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No definition available.

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Vacant space, associated with infrastructure reductions and restructuring actions, rental payments within, due after the fifth year from the balance sheet date on leases defined as operating.

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No definition available.

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- Definition

Amount of minimum lease payments for capital leases due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 30
-Section 50
-Paragraph 1
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Amount of minimum lease payments for capital leases due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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-Publisher FASB
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-Section 50
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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