Federal Income Taxes	9 Months Ended
	Sep. 30, 2021
Federal Income Taxes [Abstract]
Federal Income Taxes	6. Federal Income Taxes The effective tax rate is the ratio of tax expense (benefit) over pre-tax income (loss). The effective tax rate was 14% and 15% for the three and nine months ended September 30, 2021, respectively, compared to 13% and (7)%, respectively, for the corresponding periods in 2020. The effective tax rate on pre-tax income is typically lower than the prevailing corporate federal income tax rate of 21% due to benefits from preferential tax items including the separate accounts dividends-received deduction and tax credits. For the three months ended September 30, 2021 and September 30, 2020, the effective tax rate differed from the prevailing corporate federal income tax rate of 21% due primarily to the effects of the preferential tax items. For the nine months ended September 30, 2021, the effective tax rate differed from the prevailing corporate federal income tax rate of 21% due primarily to the effects of the preferential tax items. For the nine months ended September 30, 2020, the effective tax rate differed from the prevailing corporate federal income tax rate of 21% due primarily to the effects of preferential tax items exceeding the tax expense at 21% on pre-tax income.