Related Party Transactions (Affiliated Asset Transfers) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Related Party Transaction [Line Items]
Realized investment gains (losses)	$ (48,635)	$ (49,042)
Affiliated Entity \| DART January 2018 Purchase
Related Party Transaction [Line Items]
Fair Value	21,457
Book Value	21,457
APIC, Net of Tax Increase/(Decrease)	0
Realized investment gains (losses)	0
Affiliated Entity \| PALAC2 April 2018 Purchase
Related Party Transaction [Line Items]
Fair Value	64,313
Book Value	64,313
APIC, Net of Tax Increase/(Decrease)	0
Realized investment gains (losses)	0
Affiliated Entity \| GULRe4 May 2018 Purchase
Related Party Transaction [Line Items]
Fair Value	87,486
Book Value	87,486
APIC, Net of Tax Increase/(Decrease)	0
Realized investment gains (losses)	0
Affiliated Entity \| GULRe5 May 2018 Purchase
Related Party Transaction [Line Items]
Fair Value	37,921
Book Value	37,921
APIC, Net of Tax Increase/(Decrease)	0
Realized investment gains (losses)	0
Affiliated Entity \| PruRealtySecurities Nov 2018 Purchase
Related Party Transaction [Line Items]
Fair Value	3,259
Book Value	3,425
APIC, Net of Tax Increase/(Decrease)	0
Realized investment gains (losses)	(167)
Affiliated Entity \| PrudentialInsuranceFeb2019 Sale
Related Party Transaction [Line Items]
Fair Value	4,995
Book Value	5,000
APIC, Net of Tax Increase/(Decrease)	(4)
Realized investment gains (losses)	$ 0

Amortized Cost of assets associated with the Asset Transfer.

No definition available.

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- Definition

Fair Value of assets associated with the Asset Transfer.

+ References

No definition available.

+ Details

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- Definition

Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(30)(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.3(a))
-URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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