Intangible Assets (Details Textual) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense of intangible assets	$ 2	$ 2	$ 4	$ 4
Assets held-for-sale	$ 42		$ 42		$ 5