Number of Financial Subsidiaries

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

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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.

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- Definition

Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

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- Definition

Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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REGULATORY MATTERS - Narrative (Details) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($) subsidiary $ / shares	Sep. 30, 2016 USD ($) $ / shares	Jun. 30, 2018 $ / shares	Dec. 31, 2017 $ / shares	Sep. 30, 2017 USD ($) subsidiary $ / shares	Sep. 30, 2016 USD ($) $ / shares
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Dividends declared and paid (in Dollars per Share) \| $ / shares	$ 0.18	$ 0.12			$ 0.46	$ 0.34
Common share dividends	$ 90	$ 62			$ 233	$ 179
Preferred share dividends	7	7			14	14
Treasury stock purchased	$ 225	$ 250			$ 485	$ 250
CBNA subsidiaries
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Number of financial subsidiaries \| subsidiary	2				2
Scenario, Forecast
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Dividends declared and paid (in Dollars per Share) \| $ / shares			$ 0.22	$ 0.18
Banking Subsidiaries
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Number of financial subsidiaries \| subsidiary	2				2