Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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Namespace Prefix:	invest_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- 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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Period Type:	duration

- Definition

The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of right to receive securities 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 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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Derivative Financial Instruments (Narrative) (Details) - Swap [Member] - USD ($) $ in Millions			1 Months Ended	12 Months Ended
	Feb. 13, 2014	Aug. 09, 2013	Jan. 31, 2017	Dec. 31, 2018	Jul. 31, 2018	Jan. 31, 2018	Dec. 31, 2017	Jul. 07, 2017	Dec. 31, 2016
FFL [Member]
Derivative Financial Instruments [Line Items]
Swap agreement collateral	$ 31
Notional amount				$ 100
Term of swap agreement	1 year			1 year
FFL [Member] \| LIBOR [Member]
Derivative Financial Instruments [Line Items]
Basis spread on variable rate	1.28%			1.28%	1.05%	1.20%
AFL [Member]
Derivative Financial Instruments [Line Items]
Swap agreement collateral		$ 40
Notional amount									$ 152
Term of swap agreement		3 years	1 year
AFL [Member] \| LIBOR [Member]
Derivative Financial Instruments [Line Items]
Basis spread on variable rate		1.35%	1.28%				1.35%	1.28%