Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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-Section 55
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ 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

Aggregate amount of interest paid or due on all long-term debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.8)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of investments classified as other.

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-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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Balance Type:	debit
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- Details

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- Details

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- Details

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Balance Type:
Period Type:

- Details

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- Details

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Debt (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Debt (Details) - USD ($) $ in Millions	Jun. 30, 2018	Jun. 30, 2018	Apr. 25, 2018	Jan. 09, 2018
Debt Instrument [Line Items]
Interest Expense, Long-term Debt	$ 11	$ 20
Federal Home Loan Bank of Des Moines
Debt Instrument [Line Items]
Other investments			$ 7
Senior notes
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 1,000
Debt Instrument, Interest Rate, Stated Percentage				4.125%
Senior notes \| Senior notes, price option 1 \| Treasury Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		25.00%
Short-term debt \| Federal Home Loan Bank Advances
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 183
Debt Instrument, Interest Rate, Stated Percentage			2.16%