Reinsurance (Reinsurance Recoverable by Counterparty) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	$ 28,674,226	$ 22,691,491
PAR U
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	10,514,125	9,867,902
PALAC
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	7,706,860	0
PURC
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	3,153,449	2,324,163
PARCC
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	2,589,397	2,563,300
PAR Term
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	1,403,738	1,226,749
Prudential of Taiwan
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	1,246,241	1,169,664
Prudential Insurance
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	976,652	226,926
Term Re
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	593,084	298,002
UPARC
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	467,904	376,660
Pruco Re
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	0	4,594,412
Unaffiliated
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	$ 22,776	$ 43,713