The amount of financing receivable to held-for-investment during the reporting period.

No definition available.

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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

Represents premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield and fair value adjustments.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Represents principal amount outstanding of mortgage loans.

+ References

No definition available.

+ Details

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- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6873192&loc=d3e21338-158488

+ Details

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- Definition

The amount of financing receivables reclassified to held for sale during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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- Definition

The amount of any significant sales of financing receivables during the reporting period.

+ References

+ Details

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Balance Type:	debit
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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL49126937-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

+ Details

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Data Type:	xbrli:monetaryItemType
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Mortgage Loans Loans in Mortgage Portfolio (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Loans in Mortgage Portfolio [Line Items]
Unpaid principal balance of mortgage loans	$ 3,105,954		$ 3,105,954			$ 3,063,646
Cost basis and fair value adjustments, net	39,860		39,860			39,572
Allowance for loan losses for loans held for investment	(20,399)	$ (23,799)	(20,399)	$ (23,799)	$ (22,129)	(23,465)	$ (25,819)	$ (27,951)
Total mortgage loans	3,125,415		3,125,415			3,079,753
Carrying value of loans redesignated from HFI to HFS	2,900	1,000	5,400	1,600
Carrying value of loans redesignated from HFS to HFI	17		52
Sale of loans, unpaid principal balance	2,900	$ 1,500	3,000	$ 2,600
Single-family [Member]
Loans in Mortgage Portfolio [Line Items]
Unpaid principal balance of mortgage loans	2,861,253		2,861,253			2,833,750
Recorded investment of single-family mortgage loans referred to foreclosure	15,600		15,600			18,300
Multifamily [Member]
Loans in Mortgage Portfolio [Line Items]
Unpaid principal balance of mortgage loans	$ 244,701		$ 244,701			$ 229,896