Fair Value Measurements (Schedule of Financial Instruments Measured at Other Than Fair Value) (Details) - USD ($) $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2020		Jun. 30, 2019	Jun. 30, 2020		Jun. 30, 2019	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities	[1]	$ 293			$ 293			$ 274
Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities	[1],[2]	293	[3]		293	[3]		274
Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		293			293			274
Net loan receivables		88,833			88,833			96,094
Cash and cash equivalents	[4]	15,138			15,138			6,924
Restricted cash	[4]	29			29			40
Accrued interest receivables	[4],[5]	977			977			1,044
Time deposits	[6]	34,303			34,303			34,910
Long-term borrowings		24,002			24,002			26,572
Accrued interest payables	[4],[5]	255			255			283
Estimated Fair Value [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		12,845			12,845			14,383
Estimated Fair Value [Member] | Consolidated Entity Excluding Variable Interest Entities (VIE) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		11,157			11,157			12,189
Estimated Fair Value [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		293			293			274
Estimated Fair Value [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		0			0			0
Net loan receivables		0			0			0
Cash and cash equivalents	[4]	15,138			15,138			6,924
Restricted cash	[4]	29			29			40
Accrued interest receivables		0			0			0
Time deposits		0			0			0
Long-term borrowings		0			0			0
Accrued interest payables		0			0			0
Estimated Fair Value [Member] | Level 1 [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		0			0			0
Estimated Fair Value [Member] | Level 1 [Member] | Consolidated Entity Excluding Variable Interest Entities (VIE) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		0			0			0
Estimated Fair Value [Member] | Level 1 [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		0			0			0
Estimated Fair Value [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		293			293			274
Net loan receivables		0			0			0
Cash and cash equivalents		0			0			0
Restricted cash		0			0			0
Accrued interest receivables	[4],[5]	977			977			1,044
Time deposits	[6]	34,303			34,303			34,910
Long-term borrowings		23,858			23,858			26,400
Accrued interest payables	[4],[5]	255			255			283
Estimated Fair Value [Member] | Level 2 [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		12,701			12,701			14,211
Estimated Fair Value [Member] | Level 2 [Member] | Consolidated Entity Excluding Variable Interest Entities (VIE) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		11,157			11,157			12,189
Estimated Fair Value [Member] | Level 2 [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		293			293			274
Estimated Fair Value [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		0			0			0
Net loan receivables		88,833			88,833			96,094
Cash and cash equivalents		0			0			0
Restricted cash		0			0			0
Accrued interest receivables		0			0			0
Time deposits		0			0			0
Long-term borrowings		144			144			172
Accrued interest payables		0			0			0
Estimated Fair Value [Member] | Level 3 [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		144			144			172
Estimated Fair Value [Member] | Level 3 [Member] | Consolidated Entity Excluding Variable Interest Entities (VIE) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		0			0			0
Estimated Fair Value [Member] | Level 3 [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		0			0			0
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		284			284			272
Net loan receivables		80,743			80,743			92,511
Cash and cash equivalents	[4]	15,138			15,138			6,924
Restricted cash	[4]	29			29			40
Accrued interest receivables	[4],[5]	977			977			1,044
Time deposits	[6]	33,366			33,366			34,381
Long-term borrowings		23,194			23,194			25,701
Accrued interest payables	[4],[5]	255			255			283
Carrying Value [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		12,766			12,766			14,284
Carrying Value [Member] | Consolidated Entity Excluding Variable Interest Entities (VIE) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		10,428			10,428			11,417
Carrying Value [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		284			284			272
Fair Value, Nonrecurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Asset Impairment Charges		59		$ 0	59		$ 0
Other Short-term Investments Fair Value Disclosure	[4]	2,549			2,549
Short-term Debt, Fair Value		0			0			0
Fair Value, Nonrecurring [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Short-term Investments Fair Value Disclosure	[4]	2,549			2,549
Short-term Debt, Fair Value		0			0			0
Fair Value, Nonrecurring [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Short-term Investments Fair Value Disclosure		0			0
Short-term Debt, Fair Value		0			0			0
Fair Value, Nonrecurring [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Short-term Investments Fair Value Disclosure		0			0
Short-term Debt, Fair Value		0			0			0
Fair Value, Nonrecurring [Member] | Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Short-term Investments Fair Value Disclosure	[4]	2,549			2,549
Short-term Debt, Fair Value		$ 0			$ 0			$ 0

[1] Held-to-maturity investment securities are reported at amortized cost.

[2] Amounts represent residential mortgage-backed securities that were classified as held-to-maturity as they were entered into as a part of the Company's community reinvestment initiatives.

[3] Maturities of residential mortgage-backed securities are reflective of the contractual maturities of the investment.

[4] The carrying values of these assets and liabilities approximate fair value due to the nature of their liquidity (i.e., due or payable in less than one year).

[5] Accrued interest receivable and payable carrying values are presented as part of other assets or accrued expenses and other liabilities, respectively, in the Company's condensed consolidated statements of financial condition.

[6] Excludes deposits without contractually defined maturities for all periods presented.