Quarterly report pursuant to Section 13 or 15(d)

Derivative Instruments and Hedging Activities Interest Rate Sensitive Assets/Liabilities (Details)

v3.19.2
Derivative Instruments and Hedging Activities Interest Rate Sensitive Assets/Liabilities (Details) - USD ($)
$ in Thousands
Jun. 30, 2019
Mar. 31, 2019
Dec. 31, 2018
Jun. 30, 2018
Mar. 31, 2018
Dec. 31, 2017
Derivatives, Fair Value [Line Items]            
Available-for-sale securities, at fair value $ 30,186,079   $ 25,552,604      
Mortgage servicing rights, at fair value 1,800,826 $ 2,014,370 1,993,440 $ 1,450,261 $ 1,301,023 $ 1,086,717
Interest-Only-Strip [Member]            
Derivatives, Fair Value [Line Items]            
Available-for-sale securities, at fair value $ 147,000   $ 147,600