Convertible Debt

12 Months Ended

Dec. 31, 2015

2013 Convertible Senior Notes

On February 15, 2013, the Company repaid at maturity the entire $16.9 million outstanding balance of the 2.75% convertible senior notes due 2013 (the "2013 convertible senior notes") in accordance with the terms thereof.

2015 Convertible Senior Notes

On February 17, 2015, the Company repaid at maturity the entire $18.0 million outstanding balance of the 4.5% convertible senior notes due 2015 (the "2015 convertible senior notes") in accordance with the terms thereof. No convertible senior notes were converted to common stock.

The following table outlines the effective interest rate, contractually stated interest costs, and costs related to the amortization of issuance costs for the Company's 2013 and 2015 convertible senior notes:



	Years Ended
	December 31,
	2015	2014	2013
Effective interest rate of 2013 convertible senior notes	NA	NA	2.75%
Effective interest rate of 2015 convertible senior notes	4.50%	4.50%	4.50%
Contractually stated interest costs	$101	$810	$810
Amortization of interest costs	$7	$43	$43