Income Taxes (Details Textuals) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Income Taxes (Textuals) [Abstract]
Bad debt from acquired savings banks	$ 100
Deferred tax on bad debt from acquired savings banks	40
Unrecognized tax benefit impact on effective tax rate	6	4
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	3	2
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	1	(3)
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Operating tax loss carryforwards	287
Operating tax loss carryforwards from acquisitions	32
Tax loss carryforwards expiring in later years	$ 169