Condensed Consolidated Statements of Financial Position (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Accounts receivable, allowances	$ 31,267	$ 30,544
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, authorized (in shares)	5,000,000	5,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, par value (in shares)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	260,000,000	260,000,000
Common stock, issued (in shares)	134,199,907	135,134,064
Common stock, outstanding (in shares)	134,199,907	135,134,064