Quarterly report pursuant to Section 13 or 15(d)

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

v3.19.2
Available-for-sale Securities Classified by Rate Type (Details) - USD ($)
$ in Thousands
Jun. 30, 2019
Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]    
Adjustable Rate $ 3,607,543 $ 3,494,244
Fixed Rate 26,578,536 22,058,360
Available-for-sale securities, at fair value 30,186,079 25,552,604
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]    
Debt Securities, Available-for-sale [Line Items]    
Adjustable Rate 16,506 19,073
Fixed Rate 26,291,937 21,665,960
Available-for-sale securities, at fair value 26,308,443 21,685,033
Mortgage-backed Securities, Issued by Private Enterprises [Member]    
Debt Securities, Available-for-sale [Line Items]    
Adjustable Rate 3,591,037 3,475,171
Fixed Rate 286,599 392,400
Available-for-sale securities, at fair value $ 3,877,636 $ 3,867,571