Reinsurance - Effective Exit of GMDB and GMIB Business (Details) - Berkshire Hathway Life Insurance Company Of Nebraska [Member] - Variable Annuity [Member] $ in Billions	Dec. 31, 2018 USD ($)
Ceded Credit Risk [Line Items]
Percent of future claim payments reinsured	100.00%
Ceded Reinsurance Agreement, Coverage Limit, Amount Remaining	$ 3.4

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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