Debt (Tables)

12 Months Ended

Dec. 31, 2015

Debt

Schedule of components of interest expense incurred in connection with the entity's convertible notes

        Interest expense incurred in connection with our convertible notes consisted of the following (in thousands):

	Year Ended December 31,
	2015		2014		2013
Contractual coupon rate of interest	$	404	$	2,151	$	2,500
Discount amortization		3,020		11,057		11,178
Interest expense—convertible notes	$	3,424	$	13,208	$	13,678

Schedule of information about carrying amount of convertible notes

        The carrying value of our convertible notes consisted of the following (in thousands):

	As of December 31,
	2015			2014
Principal balance	$	5,600		$	138,750
Discount, net of accumulated amortization of $1,085 and $19,819		(213	)		(12,336	)
Carrying amount	$	5,387		$	126,414

Schedule of components of interest expense presented on the entity's consolidated statements of operations

        Details of interest expense presented on our consolidated statements of operations are as follows (in thousands):

	Year Ended December 31,
	2015		2014		2013
Interest expense	$	4,735	$	17,592	$	18,117
Less: interest capitalized		—		—		(59	)
Total interest expense	$	4,735	$	17,592	$	18,058