8. Convertible Senior Secured Notes

On May 3, 2013, the Company issued $90.0 million aggregate principal amount of Notes in a private placement offering. As of July 2017, the notes were fully converted into equity.

The Company issued the Notes under an Indenture, dated May 3, 2013 (the Indenture), between the Company and U.S. Bank National Association, as Trustee and Collateral Agent. The Notes provided for 7.50% interest per annum on the principal amount of the Notes, payable semi-annually in arrears on May 1 and November 1 of each year. The Notes would have matured on May 1, 2019, unless earlier converted, redeemed or repurchased by the Company. The Notes were convertible into the Company's common stock (Common Stock) as described in the Indenture. The conversion rate for the Notes was equal to 188.7059 shares of Common Stock per $1,000 principal amount of notes (which is equivalent to an initial conversion price of approximately $5.30 per share of Common Stock). All of the Notes have converted to Common Stock and as of December 31, 2017, there were no Notes outstanding.

The Company incurred approximately $3.5 million of financing costs (including the underwriters' fee) in connection with the issuance of the Notes. Approximately $0.9 million of this amount was allocated to additional paid-in capital and the remaining $2.6 million was recorded as a deferred cost and amortized over the term of the Notes.

The table below summarizes activity related to the Notes from issuance on May 3, 2013 through December 31, 2017, in thousands of dollars:

Gross proceeds	$	90,000
Initial value of interest make-whole derivative reported as debt discount		(9,270	)
Conversion option reported as debt discount and APIC		(22,336	)
Conversion of debt to equity—principal		(85,425	)
Conversion of debt to equity—accretion of debt discount and deferred financing costs		25,767
Accretion of debt discount and deferred financing costs		5,429

December 31, 2016 carrying value		4,165
Conversion of debt to equity—principal		(4,575	)
Conversion of debt to equity—accretion of debt discount and deferred financing costs		360
Accretion of debt discount and deferred financing costs		50

December 31, 2017 carrying value	$	—

For the year ended December 31, 2017, approximately $4.6 million aggregate principal amount of Notes were presented to the Company for conversion. Accordingly, the Company issued approximately 0.9 million shares of Common Stock in conversion of the principal amount of the Notes. As a result of the conversions, the Company incurred a loss of approximately $0.3 million on extinguishment of debt during the year ended December 31, 2017. This amount was included as a separate component of other income (expense) on the Consolidated Statement of Earnings.

For the year ended December 31, 2016, approximately $3.9 million aggregate principal amount of Notes were presented to the Company for conversion. Accordingly, the Company issued approximately 0.7 million shares of Common Stock in conversion of the principal amount of the Notes. The Company issued an additional 24,000 shares of Common Stock in settlement of the interest make-whole provision related to the converted Notes. As a result of the 2016 conversions, the Company incurred a loss on extinguishment of debt of approximately $0.7 million for the year ended December 31, 2016.