Loans Receivable, Net (Details - Modifications Types and Financial Impact) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($) loan	Dec. 31, 2017 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | loan	74	140	334
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 15	$ 28	$ 40
Re-Age Extension or Interest Capitalization with Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	9	19	25
Other with Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	0	1	2
Other without Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 6	$ 8	$ 13
One- To Four-Family [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | loan	30	49	40
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 12	$ 21	$ 18
One- To Four-Family [Member] | Re-Age Extension or Interest Capitalization with Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	6	14	13
One- To Four-Family [Member] | Other with Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	0	0	1
One- To Four-Family [Member] | Other without Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 6	$ 7	$ 4
Home Equity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | loan	44	91	294
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 3	$ 7	$ 22
Home Equity [Member] | Re-Age Extension or Interest Capitalization with Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	3	5	12
Home Equity [Member] | Other with Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	0	1	1
Home Equity [Member] | Other without Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 1	$ 9