Convertible Notes, Net (Tables)

9 Months Ended

Sep. 30, 2018

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Summary of Outstanding Convertible Senior Note

As of September 30, 2018, the following convertible senior notes, or Convertible Notes, were outstanding ($ in thousands):

Convertible Notes Issuance	Face Value		Coupon Rate			All-in Cost(1)			Conversion Rate(2)		Maturity
November 2013	$	172,328		5.25	%		5.87	%		36.5472		December 1, 2018
May 2017		402,500		4.38	%		4.85	%		28.0324		May 5, 2022
March 2018		220,000		4.75	%		5.33	%		27.6052		March 15, 2023

(1)

Includes issuance costs that are amortized through interest expense over the life of the Convertible Notes using the effective interest method.

(2)

Represents the shares of class A common stock per $1,000 principal amount of Convertible Notes, which is equivalent to a conversion price of $27.36, $35.67, and $36.23 per share of class A common stock, respectively, for the November 2013, May 2017, and March 2018 convertible notes. As a result of exceeding the cumulative dividend threshold, as defined in the November 2013 convertible notes supplemental indenture, the conversion rate on the November 2013 convertible notes was most recently adjusted on March 28, 2018 from the prior conversion rate of 36.1380 shares of class A common stock per $1,000 principal amount of convertible notes, which was equivalent to a conversion price of $27.67 per share of class A common stock. Pursuant to the terms of the November 2013 supplemental indenture, the conversion rate will be adjusted to 36.8161 on the first day of any future observation period related to a conversion of the November 2013 convertible notes to account for the dividends paid on our class A common stock on July 16, 2018 and October 15, 2018. The cumulative dividend threshold as defined in the respective May 2017 and March 2018 convertible notes supplemental indentures have not been exceeded as of September 30, 2018.

Summary of Details of Net Book Value of Convertible Note

The following table details the net book value of our Convertible Notes on our consolidated balance sheets ($ in thousands):

	September 30, 2018			December 31, 2017
Face value	$	794,828		$	575,000
Unamortized discount		(12,956	)		(10,279	)
Deferred financing costs		(921	)		(810	)
Net book value	$	780,951		$	563,911

Summary of Details about Interest Expense

The following table details our interest expense related to the Convertible Notes ($ in thousands):

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2018		2017		2018		2017
Cash coupon	$	9,277	$	6,247	$	25,333	$	12,732
Discount and issuance cost amortization		1,535		1,202		4,242		2,869
Total interest expense	$	10,812	$	7,449	$	29,575	$	15,601