Leasing (Investments In Operating Leases) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Jan. 01, 2019
Operating Leased Assets [Line Items]
Lessee, operating lease, remaining lease term, minimum	6 months
Lessee, operating lease, remaining lease term, maximum	13 years
Lessee, operating lease, option to extend, minimum	1 year
Lessee, operating lease, option to extend, maximum	15 years
Lessee, operating lease, option to terminate, minimum	2 years
Lessee, operating lease, option to terminate, maximum	5 years
Lessee, operating lease, noncancellable lease term	367 days
Lessee, operating lease, lease extension, maximum	48 months
Operating Lease, Right-of-Use Asset	$ 177
Operating Lease, Liability	206
Cash paid for amounts included in the measurement of lease liabilities	$ 12
Operating lease, weighted-average remaining lease term	7 years
Operating lease, weighted average discount rate	2.98%
Leasing Arrangement [Member]
Operating Leased Assets [Line Items]
Operating Lease, Right-of-Use Asset	$ 27
Accounting Standards Update 2016-02
Operating Leased Assets [Line Items]
Operating Lease, Right-of-Use Asset		$ 161
Operating Lease, Liability		$ 190