Commitments and Contingencies - Fair Value of Annuities (Detail) $ in Thousands	Dec. 31, 2022 USD ($)
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	$ 99,667
Pacific Life Insurance Company [Member] | A.M. Best Rating, A+ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	19,007
American General Life Insurance Company [Member] | A.M. Best Rating, A [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	14,314
Metropolitan Tower Life Insurance Company [Member] | A.M. Best Rating, A+ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	9,563
United of Omaha Life Insurance Company [Member] | A.M. Best Rating, A+ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	9,408
Brighthouse Financial Life Insurance Company [Member] | A.M. Best Rating, A [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	9,312
New York Life Insurance Company [Member] | A.M. Best Rating, A++ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	8,128
Berkshire Hathaway Life Insurance Company of Nebraska [Member] | A.M. Best Rating, A++ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	7,343
John Hancock Life Insurance Company [Member] | A.M. Best Rating, A+ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	5,767
Athene Annuity and Life Company [Member] | A.M. Best Rating, A [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	3,739
Protective Life Insurance Company [Member] | A.M. Best Rating, A+ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	3,537
Wilton Reassurance Company member | A.M. Best Rating, A+ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	3,057
Other [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	$ 6,492