Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Accounts receivable, allowance	$ 0	$ 0
Common stock, par value	$ 0.00000625	$ 0.00000625
Common stock, shares authorized	2,020,517,000	2,020,517,000
Common stock, shares outstanding	862,213,000	886,850,000
Common Class A [Member]
Common stock, shares outstanding	771,535,000	770,269,000
Common Class B [Member]
Common stock, shares outstanding	70,161,000	96,064,000
Common Class C [Member]
Common stock, shares outstanding	20,517,000	20,517,000