Investments (Accrued Investment Income) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Net Investment Income
Accrued investment income	$ 99,519	$ 121,604
Fixed maturities
Net Investment Income
Accrued investment income	93,436	116,342
Equity Securities
Net Investment Income
Accrued investment income	60	1
Commercial mortgage and other loans
Net Investment Income
Accrued investment income	5,091	4,828
Policy loans
Net Investment Income
Accrued investment income	11	11
Short-term investments and cash equivalents
Net Investment Income
Accrued investment income	649	158
Other
Net Investment Income
Accrued investment income	$ 272	$ 264

Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(4))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 2: 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(3))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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