Condensed Consolidated Statements of Operations and Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Mortgage loans (includes $27,058 and $25,168, respectively, for the three months ended and $79,877 and $75,155, respectively, for the nine months ended related to consolidated trusts)	$ 28,723	$ 27,047	$ 85,064	$ 81,105
Long-term debt (includes $22,361 and $20,609, respectively, for the three months ended and $65,972 and $61,622, respectively, for the nine months ended related to consolidated trusts)	23,861	22,115	70,406	66,443
Consolidated Trusts [Member]
Mortgage loans (includes $27,058 and $25,168, respectively, for the three months ended and $79,877 and $75,155, respectively, for the nine months ended related to consolidated trusts)	27,058	25,168	79,877	75,155
Long-term debt (includes $22,361 and $20,609, respectively, for the three months ended and $65,972 and $61,622, respectively, for the nine months ended related to consolidated trusts)	$ 22,361	$ 20,609	$ 65,972	$ 61,622