Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Allowances for accounts receivable	$ 251,414	$ 167,411
Deferred finance costs, noncurrent, net	$ 40,768	$ 47,174
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	1,725,000	1,725,000
Preferred stock, shares outstanding	1,725,000	1,725,000
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	54,804,000	54,294,000
Common stock, shares outstanding	54,804,000	54,294,000