Derivative and Hedging Activities (Details Textuals) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Investment securities and cash equivalents pledged as collateral	$ 80	$ 57
Derivative collateral right to reclaim cash	36	14
Designated as Hedging Instrument
Balance Sheet Recording of Fair Value Hedge [Line Items]
Derivative Liability Notional Amount, Terminated		$ 500
Underlying Hedged Asset, Amortized Cost Basis	829
Deferred (Gain) Loss on Discontinuation of Fair Value Hedge	$ 5

[Line Items] for Balance Sheet Recording of Fair Value Hedge [Table]

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- Definition

Derivative Liability Notional Amount, Terminated

+ References

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- Definition

Underlying Hedged Asset, Amortized Cost Basis

+ References

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- Definition

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959

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- Definition

Amount as of the balance sheet date of the unamortized adjustment to the carrying value of an interest-bearing hedged item made under an effective fair value hedge that is amortized upon discontinuation of the fair value hedge.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 35
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=118957181&loc=d3e75592-113984

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=d3e41678-113959

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- References

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