Separation Activities and Initial Public Offering (Initial Public Offering) (Details) (USD $)	Jun. 30, 2013	Jun. 30, 2013 Common Class A [Member]	Jun. 30, 2013 Common Class B [Member]	Feb. 06, 2013 IPO [Member] Common Class A [Member]
Class of Stock [Line Items]
Common stock, shares issued	500,000,000			99,015,000
Share price				$ 26.00
Common stock, shares outstanding	500,000,000	99,015,000	400,985,000