Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Operating Activities
Net income	$ 194	$ 221
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	0	70
Net change in derivatives and hedging activities	(670)	268
Net change in fair value adjustments on trading securities	(2)	2
Net impairment losses recognized in earnings	3	1
Net change in:
Accrued interest receivable	(12)	(90)
Other assets	25	30
Affordable Housing Program payable	2	3
Accrued interest payable	27	30
Other liabilities	(28)	(34)
Total adjustments	(655)	280
Net cash (used in) provided by operating activities	(461)	501
Investing activities
Interest-bearing deposits	3,065	(1,701)
Securities purchased under agreements to resell	(750)	0
Federal funds sold	(1,232)	(4,338)
Loan to another FHLBank	500	200
Trading securities:
Purchases of long-term	(1,499)	0
Proceeds from Sale and Maturity of Debt Securities, Available-for-sale [Abstract]
Proceeds from principal collected	96	117
Held-to-maturity securities:
Proceeds from principal collected	1,908	2,700
Purchases of long-term	(3,780)	(3,956)
Advances:
Proceeds from principal collected	195,145	229,834
Made	(187,712)	(232,365)
Mortgage loans:
Proceeds from principal collected	32	40
Proceeds from sale of foreclosed assets	1	1
Purchase of premises, equipment, and software	(1)	(2)
Net cash provided by (used in) investing activities	5,773	(9,470)
Financing activities
Net change in interest-bearing deposits	237	(141)
Net payments on derivatives containing a financing element	(1)	(3)
Proceeds from issuance of consolidated obligations:
Discount notes	531,999	554,778
Bonds	42,555	40,185
Payments for debt issuance costs	(6)	(6)
Payments for maturing and retiring consolidated obligations:
Discount notes	(533,211)	(539,662)
Bonds	(46,369)	(47,737)
Proceeds from issuance of capital stock	4,931	6,132
Payments for repurchase/redemption of capital stock	(5,221)	(5,953)
Payments for repurchase/redemption of mandatorily redeemable capital stock	0	(32)
Cash dividends paid	(166)	(145)
Net cash (used in) provided by financing activities	(5,252)	7,416
Net increase (decrease) in cash and due from banks	60	(1,553)
Cash and due from banks at beginning of the period	35	2,357
Cash and due from banks at end of the period	95	804
Cash paid for:
Interest	1,660	1,096
Affordable Housing Program assessment, net	19	21
Noncash investing and financing activities:
Net shares reclassified to mandatorily redeemable capital stock	0	33
Held-to-maturity securities acquired with accrued liabilities	114	0
Transfers of mortgage loans to real estate owned	$ 0	$ 1