Quarterly report pursuant to Section 13 or 15(d)

Derivative Instruments and Hedging Activities Credit Risk - Counterparty Exposure (Details)

v3.8.0.1
Derivative Instruments and Hedging Activities Credit Risk - Counterparty Exposure (Details) - USD ($)
$ in Thousands
Mar. 31, 2018
Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]    
Derivative assets, at fair value $ 274,048 $ 309,918
Derivative liabilities, at fair value $ 46,074 $ 31,903