Reinsurance - Effective Exit of GMDB and GMIB Business (Details) - Berkshire Hathway Life Insurance Company Of Nebraska [Member] - Variable Annuity [Member] - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2016
Ceded Credit Risk [Line Items]
Reinsurance preimums paid	$ 2.2
Percent of future claim payments reinsured	100.00%
Ceded Reinsurance Agreement, Coverage Limit, Amount Remaining		$ 3.5