Related Party Transactions (Affiliated Asset Transfers) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Related Party Transaction [Line Items]
Realized investment (gains) losses, net	$ (836,964)	$ (3,375,764)	$ 2,292,172	$ (4,133,455)
Affiliated Entity | Prudential International Insurance Service Company March 2020 - Purchase
Related Party Transaction [Line Items]
Fair Value	107,014		107,014
Book Value	107,014		107,014
APIC, Net of Tax Increase/(Decrease)	0		0
Realized investment (gains) losses, net			0
Affiliated Entity | Prudential Insurance March 2020 Purchase
Related Party Transaction [Line Items]
Fair Value	258,885		258,885
Book Value	258,885		258,885
APIC, Net of Tax Increase/(Decrease)	0		0
Realized investment (gains) losses, net			0
Affiliated Entity | Prudential Insurance April 2020 Purchase
Related Party Transaction [Line Items]
Fair Value	91,131		91,131
Book Value	91,131		91,131
APIC, Net of Tax Increase/(Decrease)	0		0
Realized investment (gains) losses, net			0
Affiliated Entity | Prudential Insurance June 2020 Sale
Related Party Transaction [Line Items]
Fair Value	65,646		65,646
Book Value	57,699		57,699
APIC, Net of Tax Increase/(Decrease)	0		0
Realized investment (gains) losses, net			7,947
Affiliated Entity | Gibraltar life insurance company June 2020 Purchase
Related Party Transaction [Line Items]
Fair Value	222,091		222,091
Book Value	222,091		222,091
APIC, Net of Tax Increase/(Decrease)	0		0
Realized investment (gains) losses, net			0
Affiliated Entity | Prudential Insurance April 2021 Purchase
Related Party Transaction [Line Items]
Fair Value	200,873		200,873
Book Value	200,873		200,873
APIC, Net of Tax Increase/(Decrease)	0		0
Realized investment (gains) losses, net			0
Affiliated Entity | Prudential Insurance April 2021 Purchase
Related Party Transaction [Line Items]
Fair Value	176,904		176,904
Book Value	176,904		176,904
APIC, Net of Tax Increase/(Decrease)	0		0
Realized investment (gains) losses, net			0
Affiliated Entity | Vantage Casualty Insurance Co June 2021 Purchase
Related Party Transaction [Line Items]
Fair Value	14,662		14,662
Book Value	14,662		14,662
APIC, Net of Tax Increase/(Decrease)	0		0
Realized investment (gains) losses, net			0
Affiliated Entity | Prudential Insurance June 2021 Sale
Related Party Transaction [Line Items]
Fair Value	3,050		3,050
Book Value	3,013		3,013
APIC, Net of Tax Increase/(Decrease)	0		0
Realized investment (gains) losses, net			37
Affiliated Entity | Pruco Life June 2021 Sale
Related Party Transaction [Line Items]
Fair Value	40,284		40,284
Book Value	38,026		38,026
APIC, Net of Tax Increase/(Decrease)	0		0
Realized investment (gains) losses, net			2,258
Affiliated Entity | Passaic Fund LLC June 2021 Sale
Related Party Transaction [Line Items]
Fair Value	12,350		12,350
Book Value	12,350		12,350
APIC, Net of Tax Increase/(Decrease)	$ 0		0
Realized investment (gains) losses, net			$ 0