Reinsurance (Reinsurance Recoverable by Counterparty) (Details) - USD ($) $ in Thousands	Sep. 30, 2020		Dec. 31, 2019
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	$ 51,051,073	[1]	$ 40,710,159
PAR U
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	13,106,456		12,380,683
PALAC
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	19,031,724		11,635,405
PURC
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	5,212,049		4,692,769
PARCC
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	2,519,113		2,627,595
GUL Re
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	2,498,242		2,292,638
PAR Term
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	1,884,370		1,825,594
Prudential Insurance
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	2,687,057		1,764,512
Prudential of Taiwan
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	1,590,112		1,499,685
Term Re
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	1,689,778		1,506,366
DART
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	468,851		327,235
Unaffiliated
Effects of Reinsurance [Line Items]
Total reinsurance recoverables	$ 363,321		$ 157,677

[1] September 30, 2020 amounts include the impacts of the January 1, 2020 adoption of ASU 2016-13. See Note 2 for details.