CONSOLIDATED STATEMENTS OF FINANCIAL CONDITION (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Cash Collateral for Borrowed Securities	$ 1,025,431	$ 1,648,545
Pledged Financial Instruments, Not Separately Reported, Securities	$ 2,096,223	$ 3,240,583
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	85,150,000	85,150,000
Preferred Stock, Shares Issued	81,900,000	81,900,000
Preferred Stock, Shares Outstanding	81,900,000	81,900,000
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	2,914,850,000	2,914,850,000
Common Stock, Shares, Issued	1,402,928,317	1,430,106,199
Common Stock, Shares, Outstanding	1,402,928,317	1,430,106,199
Non-Agency Mortgage-Backed Securities
Pledged assets	$ 3,431	$ 3,336
Agency Mortgage-Backed Securities
Pledged assets	$ 67,664,458	$ 108,809,569