Reinsurance - Effective Exit of GMDB and GMIB Business (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Ceded Credit Risk [Line Items]
Ceded Reinsurance Agreement Charge, After-tax				$ 507
Ceded Reinsurance Agreement Charge, Pre-tax				781
Reinsurance preimums paid		$ 0	$ 0	2,196
Other Benefits Expense [Member]
Ceded Credit Risk [Line Items]
Ceded Reinsurance Agreement Charge, Pre-tax				727
Other Operating Expenses [Member]
Ceded Credit Risk [Line Items]
Ceded Reinsurance Agreement Charge, Pre-tax				54
Berkshire Hathway Life Insurance Company Of Nebraska [Member] | Variable Annuity [Member]
Ceded Credit Risk [Line Items]
Percent of future claim payments reinsured		100.00%
Ceded Reinsurance Agreement, Coverage Limit, Amount Remaining		$ 3,600
Ceded Reinsurance Agreement Charge, After-tax	$ 507
Ceded Reinsurance Agreement Charge, Pre-tax	781
Reinsurance preimums paid	2,200
Berkshire Hathway Life Insurance Company Of Nebraska [Member] | Variable Annuity [Member] | Guaranteed Minimum Death Benefit [Member]
Ceded Credit Risk [Line Items]
Reinsurance preimums paid				$ 1,647
Berkshire Hathway Life Insurance Company Of Nebraska [Member] | Other Benefits Expense [Member] | Variable Annuity [Member]
Ceded Credit Risk [Line Items]
Ceded Reinsurance Agreement Charge, Pre-tax	727
Berkshire Hathway Life Insurance Company Of Nebraska [Member] | Other Operating Expenses [Member] | Variable Annuity [Member]
Ceded Credit Risk [Line Items]
Ceded Reinsurance Agreement Charge, Pre-tax	54
Berkshire Hathway Life Insurance Company Of Nebraska [Member] | Guaranteed Minimum Income Benefits Fair Value Gain Loss [Member] | Variable Annuity [Member]
Ceded Credit Risk [Line Items]
Ceded Reinsurance Agreement Charge, After-tax	$ 45