Income Taxes	3 Months Ended
	Mar. 31, 2022
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The effective tax rate was 7.3 percent for the three months ended March 31, 2022, compared with 8.2 percent for the three months ended March 31, 2021. The lower effective tax rate for the three months ended March 31, 2022 was largely driven by decreased tax expense related to net investment losses on equity securities compared to net investment gains on equity securities for the three months ended March 31, 2021 and decreased tax expense related to the implementation of the provision in the Tax Cuts and Jobs Act (the 2017 Tax Act) that requires capitalization and amortization of research and development expenses for tax purposes starting in 2022, partially offset by a lower net discrete tax benefit compared to the three months ended March 31, 2021. If this provision of the 2017 Tax Act is deferred or repealed by Congress effective for 2022, we expect our effective tax rate to be approximately 13 percent to 14 percent for 2022.The U.S. examination of tax years 2016-2018 began in the fourth quarter of 2019 and remains ongoing. The resolution of this audit period will likely extend beyond the next 12 months.