Customer Deposits (Details 3) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Time Deposits $250,000 Or More [Line Items]
Time Deposits, $100,000 or More	$ 158	$ 125
United States [Member]
Time Deposits $250,000 Or More [Line Items]
Time Deposits, $100,000 or More	146	114
Non Us [Member]
Time Deposits $250,000 Or More [Line Items]
Time Deposits, $100,000 or More	$ 12	$ 11