Quarterly report pursuant to Section 13 or 15(d)

Available-for-Sale Securities, at Fair Value Schedule of Available-for-sale Debt Securities in Unrealized Loss Positions (Details)

v3.20.2
Available-for-Sale Securities, at Fair Value Schedule of Available-for-sale Debt Securities in Unrealized Loss Positions (Details)
$ in Thousands
Jun. 30, 2020
USD ($)
numberOfPositions
Dec. 31, 2019
USD ($)
numberOfPositions
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Number of Positions | numberOfPositions 835 1,237
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions | numberOfPositions 8 122
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | numberOfPositions 13 151
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months $ 21,111 $ 3,970,743
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (4,367) (25,061)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 15,043 735,727
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss (695) (62,932)
Debt Securities, Available-for-sale, Unrealized Loss Position 36,154 4,706,470
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 5,062 87,993
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]    
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 21,111 3,322,894
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (4,367) (6,645)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 15,043 524,739
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss (695) (49,521)
Debt Securities, Available-for-sale, Unrealized Loss Position 36,154 3,847,633
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 5,062 56,166
Mortgage-backed Securities, Issued by Private Enterprises [Member]    
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 0 647,849
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 0 (18,416)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 0 210,988
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 0 (13,411)
Debt Securities, Available-for-sale, Unrealized Loss Position 0 858,837
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss $ 0 $ 31,827