Consolidated Condensed Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Trade accounts receivable, allowance for doubtful accounts (in dollars)	$ 4,814	$ 4,634
Property and equipment, accumulated depreciation	179,956	145,274
Definite lived intangible assets, accumulated amortization	$ 183,625	$ 138,072
Preferred stock par value (in dollars per share)	$ 0	$ 0
Preferred stock, shares authorized (in shares)	50,000,000	50,000,000
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	129,322,905	128,600,384