Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net earnings, including noncontrolling interests	$ 668	$ 370	$ 406
Net unrealized gains (losses) on securities:
Unrealized holding gains (losses) on securities arising during the period	80	(406)	216
Reclassification adjustment for realized (gains) losses included in net earnings	(12)	9	(33)
Reclassification for unrealized gains of subsidiaries sold	0	(22)	0
Total net unrealized gains (losses) on securities	68	(419)	183
Net unrealized gains (losses) on cash flow hedges	(8)	1	0
Foreign currency translation adjustments	7	(14)	(9)
Pension and other postretirement plans adjustments	0	1	(4)
Other comprehensive income (loss), net of tax	67	(431)	170
Total comprehensive income (loss), net of tax	735	(61)	576
Less: Comprehensive income (loss) attributable to noncontrolling interests	24	10	(43)
Comprehensive income (loss) attributable to shareholders	$ 711	$ (71)	$ 619