Unsecured Senior Notes

6 Months Ended

Jun. 30, 2019

10. Unsecured Senior Notes

The following table is a summary of our unsecured senior notes outstanding as of June 30, 2019 and December 31, 2018 (dollars in thousands):


						Remaining
	Coupon		Effective		Maturity	Period of		Carrying Value at
	Rate		Rate (1)		Date	Amortization		June 30, 2019		December 31, 2018
2019 Convertible Notes	N/A		N/A		N/A	N/A		$	—	$	77,969
2021 Senior Notes (February)	3.63	%	3.89	%	2/1/2021	1.6	years		500,000		500,000
2021 Senior Notes (December)	5.00	%	5.32	%	12/15/2021	2.5	years		700,000		700,000
2023 Convertible Notes	4.38	%	4.86	%	4/1/2023	3.8	years		250,000		250,000
2025 Senior Notes	4.75	%	5.04	%	3/15/2025	5.7	years		500,000		500,000
Total principal amount									1,950,000		2,027,969
Unamortized discount—Convertible Notes									(4,118)		(4,644)
Unamortized discount—Senior Notes									(14,301)		(16,416)
Unamortized deferred financing costs									(6,870)		(8,078)
Carrying amount of debt components								$	1,924,711	$	1,998,831
Carrying amount of conversion option equity components recorded in additional paid-in capital for outstanding convertible notes								$	3,755	$	3,755

(1)	Effective rate includes the effects of underwriter purchase discount and the adjustment for the conversion option on our Convertible Notes, the value of which reduced the initial liability and was recorded in additional paid-in capital.

Convertible Senior Notes

During the six months ended June 30, 2019, we settled the remaining $78.0 million principal amount of the 4.00% Convertible Senior Notes due 2019 (the “2019 Notes”) through the issuance of 3.6 million shares of common stock and cash payments of $12.0 million.

We recognized interest expense of $3.0 million and $6.2 million during the three and six months ended June 30, 2019, respectively, from our unsecured Convertible Notes. We recognized interest expense of $7.6 million and $18.9 million during the three and six months ended June 30, 2018, respectively, from our unsecured Convertible Notes.

The following table details the conversion attributes of our Convertible Notes outstanding as of June 30, 2019 (amounts in thousands, except rates):


	June 30, 2019			Conversion Spread Value - Shares (3)
	Conversion	Conversion		For the Three Months Ended June 30,		For the Six Months Ended June 30,
	Rate (1)	Price (2)		2019	2018	2019	2018
2019 Notes	N/A		N/A	—	1,863	—	1,900
2023 Notes	38.5959	$	25.91	—	—	—	—
				—	1,863	—	1,900

(1)	The conversion rate represents the number of shares of common stock issuable per $1,000 principal amount of Convertible Notes converted, as adjusted in accordance with the indentures governing the Convertible Notes (including the applicable supplemental indentures).

(2)	As of June 30, 2019 and 2018, the market price of the Company’s common stock was $22.72 and $21.71 per share, respectively.

(3)	The conversion spread value represents the portion of the Convertible Notes that are “in-the-money”, representing the value that would be delivered to investors in shares upon an assumed conversion.

The if-converted value of the 2023 Notes was less than their principal amount by $30.8 million at June 30, 2019 as the closing market price of the Company’s common stock of $22.72 was less than the implicit conversion price of $25.91 per share.

Effective June 30, 2018, the Company no longer asserts its intent to fully settle the principal amount of the Convertible Notes in cash upon conversion. The if-converted value of the principal amount of the 2023 Notes was $219.2 million as of June 30, 2019.