Loans Receivable, Net (Details - Allowance) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jan. 01, 2020
Financing Receivable, Allowance for Credit Losses, Additional Information [Line Items]
Allowance for loan losses, beginning of period	$ (86)	$ 32	$ 17	$ 37
Cumulative Effect on Retained Earnings, before Tax			(114)
Provision (benefit) for credit losses	(1)	(8)	5	(20)
Charge-offs	0	(1)	0	(2)
Recoveries	5	7	10	15
Net (charge-offs) recoveries	5	6	10	13
Allowance for loan losses, end of period	(82)	30	(82)	30
Allowance for loan losses	(86)	30	(82)	30
One- To Four-Family [Member]
Financing Receivable, Allowance for Credit Losses, Additional Information [Line Items]
Allowance for loan losses, beginning of period	(35)	9	6	9
Cumulative Effect on Retained Earnings, before Tax			(43)
Provision (benefit) for credit losses	(1)	(1)	0	(3)
Charge-offs	0	0	0	0
Recoveries	0	1	1	3
Net (charge-offs) recoveries	0	1	1	3
Allowance for loan losses, end of period	(36)	9	(36)	9
Benefit from Fair Value Appreciation Loans					$ 39
Allowance for loan losses	(35)	9	6	9	(37)
Home Equity [Member]
Financing Receivable, Allowance for Credit Losses, Additional Information [Line Items]
Allowance for loan losses, beginning of period	(51)	21	11	26
Cumulative Effect on Retained Earnings, before Tax			(71)
Provision (benefit) for credit losses	0	(8)	5	(18)
Charge-offs	0	0	0	0
Recoveries	5	6	9	11
Net (charge-offs) recoveries	5	6	9	11
Allowance for loan losses, end of period	(46)	19	(46)	19
Benefit from Fair Value Appreciation Loans					70
Allowance for loan losses	$ (46)	19	$ (46)	19	$ (60)
Consumer and other [Member]
Financing Receivable, Allowance for Credit Losses, Additional Information [Line Items]
Allowance for loan losses, beginning of period		2		2
Provision (benefit) for credit losses		1		1
Charge-offs		(1)		(2)
Recoveries		0		1
Net (charge-offs) recoveries		(1)		(1)
Allowance for loan losses, end of period		2		2
Allowance for loan losses		$ 2		$ 2

Benefit from Fair Value Appreciation of Underlying Collateral for Loans.

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount, after recoveries, of loans and leases that have been written-off.

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Amount of the cumulative effect on retained earnings before related income tax effect.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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