Convertible Notes (Tables)

12 Months Ended

Dec. 31, 2015

Convertible Notes

Schedule of components of convertible notes

				Carrying Amount,
	Interest Rates			December 31,
Debt	December 31, 2015		Maturities	2015		2014
4.75% Convertible Senior Notes due 2015	4.75	%	2015	$	—	$	85,186
0.375% Convertible Senior Notes due 2018	0.375	%	2018		324,031		307,978
1.25% Convertible Senior Notes due 2020	1.25	%	2020		295,862		282,003
					619,893		675,167
Less current portion					—		85,186
				$	619,893	$	589,981

Schedule of annual maturities of convertible notes

2016	$	—
2017		—
2018		375.0
2019		—
2020		374.8
Thereafter		—
	$	749.8

Schedule of carrying amount and fair value of convertible notes

	December 31,
	2015				2014
	Carrying				Carrying
	Amount		Fair Value		Amount		Fair Value
4.75% Convertible Senior Notes due 2015	$	—	$	—	$	85,186	$	755,143
0.375% Convertible Senior Notes due 2018		324,031		807,422		307,978		560,156
1.25% Convertible Senior Notes due 2020		295,862		816,123		282,003		577,736
	$	619,893	$	1,623,545	$	675,167	$	1,893,035