Trading Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Schedule of Trading Securities [Line Items]
Trading securities	$ 5,699,070	$ 4,707,975
Trading Securities, Net Unrealized Gain (Loss)	(9,644)	(3,560)
U.S. government securities [Member]
Schedule of Trading Securities [Line Items]
Trading securities	13,481	9,183
Trading Securities, Net Unrealized Gain (Loss)	(1)	0
Residential agency mortgage-backed securities [Member]
Schedule of Trading Securities [Line Items]
Trading securities	5,577,986	4,669,148
Trading Securities, Net Unrealized Gain (Loss)	(9,598)	(3,624)
Municipal securities [Member]
Schedule of Trading Securities [Line Items]
Trading securities	49,636	19,172
Trading Securities, Net Unrealized Gain (Loss)	(20)	42
Other debt securities [Member]
Schedule of Trading Securities [Line Items]
Trading securities	57,967	10,472
Trading Securities, Net Unrealized Gain (Loss)	$ (25)	$ 22