Annual report pursuant to Section 13 and 15(d)

Available-for-sale Securities Classified by Rate Type (Details)

v3.19.3.a.u2
Available-for-sale Securities Classified by Rate Type (Details) - USD ($)
$ in Thousands
Dec. 31, 2019
Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]    
Adjustable Rate $ 3,358,871 $ 3,494,244
Fixed Rate 28,047,457 22,058,360
Available-for-sale securities, at fair value 31,406,328 25,552,604
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]    
Debt Securities, Available-for-sale [Line Items]    
Adjustable Rate 14,584 19,073
Fixed Rate 27,763,471 21,665,960
Available-for-sale securities, at fair value 27,778,055 21,685,033
Mortgage-backed Securities, Issued by Private Enterprises [Member]    
Debt Securities, Available-for-sale [Line Items]    
Adjustable Rate 3,344,287 3,475,171
Fixed Rate 283,986 392,400
Available-for-sale securities, at fair value $ 3,628,273 $ 3,867,571