Commitments and Contingent Liabilities (Operating Leases) (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Commitments and Contingent Liabilities [Abstract]
Future minimum lease payments for 2013	$ 320
Future minimum lease payments for 2014	260
Future minimum lease payments for 2015	213
Future minimum lease payments for 2016	178
Future minimum lease payments for 2017	153
Future minimum lease payments for subsequent years	290
Future minimum sublease rental income	3
Net rental expense under operating leases	$ 316	$ 268	$ 229