Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Total Controlling Interest Shareholders' Equity [Member]	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interest [Member]
Balance, beginning of period at Dec. 31, 2012	$ 1,419,414	$ 1,393,385	$ 932,742	$ 476,310	$ (15,667)	$ 26,029
Balance, beginning of period (in shares) at Dec. 31, 2012			105,763,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	113,049	109,922		109,922		3,127
Foreign currency translation adjustments	4,970	4,970			4,970
Unrealized gain (loss) on hedges, net	(9,991)	(9,991)			(9,991)
Distributions to noncontrolling interests	(4,097)					(4,097)
Equity component of debt discount on Convertible Senior Notes due 2032	49	49	$ 49
Stock compensation expense	7,510	7,510	7,510
Stock repurchases	(8,855)	(8,855)	$ (8,855)
Stock repurchases (in shares)			(390,000)
Activity in company stock plans, net and other	1,842	1,842	$ 1,842
Activity in company stock plans, net and other (in shares)			267,000
Excess tax from stock-based compensation	219	219	$ 219
Balance, end of period at Dec. 31, 2013	1,524,110	1,499,051	$ 933,507	586,232	(20,688)	25,059
Balance, end of period (in shares) at Dec. 31, 2013			105,640,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	195,550	195,047		195,047		503
Foreign currency translation adjustments	(19,464)	(19,464)			(19,464)
Unrealized gain (loss) on hedges, net	(22,100)	(22,100)			(22,100)
Distributions to noncontrolling interests	(1,018)					(1,018)
Acquisition of noncontrolling interests	(21,646)	2,898	$ 2,898			(24,544)
Stock compensation expense	2,176	2,176	2,176
Stock repurchases	(7,698)	(7,698)	$ (7,698)
Stock repurchases (in shares)			(321,000)
Activity in company stock plans, net and other	3,496	3,496	$ 3,496
Activity in company stock plans, net and other (in shares)			267,000
Excess tax from stock-based compensation	68	68	$ 68
Balance, end of period at Dec. 31, 2014	1,653,474	1,653,474	$ 934,447	781,279	(62,252)	0
Balance, end of period (in shares) at Dec. 31, 2014			105,586,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(376,980)	(376,980)		(376,980)
Foreign currency translation adjustments	(12,849)	(12,849)			(12,849)
Unrealized gain (loss) on hedges, net	4,200	4,200			4,200
Stock compensation expense	5,463	5,463	$ 5,463
Cumulative stock compensation expense in excess of fair value of modified liability awards	$ 2,915	2,915	2,915
Stock repurchases (in shares)	(3,589,425)
Activity in company stock plans, net and other	$ 3,443	3,443	$ 3,443
Activity in company stock plans, net and other (in shares)			703,000
Excess tax from stock-based compensation	(703)	(703)	$ (703)
Balance, end of period at Dec. 31, 2015	$ 1,278,963	$ 1,278,963	$ 945,565	$ 404,299	$ (70,901)	$ 0
Balance, end of period (in shares) at Dec. 31, 2015			106,289,000