Offsetting Assets and Liabilities - Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Effect of offsetting recognized liabilities, Derivative
Gross Amounts of Recognized Liabilities, Derivative	$ 11,906	$ 3,625
Effect of offsetting recognized liabilities, Total
Gross Amounts of Recognized Liabilities, Total	1,327,440	838,172
Liabilities Presented in the Consolidated Balance Sheets, Total	1,327,440	838,172
Financial Instruments, Total	1,315,534	834,547
Cash Collateral Paid, Total	11,906	3,625
Interest Rate Swap Agreement
Effect of offsetting recognized liabilities, Derivative
Gross Amounts of Recognized Liabilities, Derivative	11,849	3,625
Liabilities Presented in the Consolidated Balance Sheets, Derivative	11,849	3,625
Cash Collateral Paid, Derivative	11,849	3,625
Credit default swaps
Effect of offsetting recognized liabilities, Derivative
Gross Amounts of Recognized Liabilities, Derivative	57
Liabilities Presented in the Consolidated Balance Sheets, Derivative	57
Cash Collateral Paid, Derivative	57
Secured borrowings
Effect of offsetting recognized liabilities, Borrowings
Gross Amounts of Recognized Liabilities, Borrowings	1,315,534	834,547
Liabilities Presented in the Consolidated Balance Sheets, Borrowings	1,315,534	834,547
Financial Instruments, Borrowings	$ 1,315,534	$ 834,547

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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