Note 5 - Long-Term Debt

Credit Agreement

The Company’s Fifth Amended and Restated Credit Agreement, as amended, (the “Credit Agreement”) provides for a maximum loan amount of $2.5 billion and has a maturity date of December 10, 2019. As of March 31, 2018, the Company’s borrowing base and aggregate lender commitments were $925 million, which were unchanged from December 31, 2017. Subsequent to March 31, 2018, as part of the regular, semi-annual borrowing base redetermination process, the borrowing base and aggregate lender commitments were increased to $1.4 billion and $1.0 billion, respectively. The increase in the borrowing base was primarily driven by the increased value of the Company’s estimated proved reserves at December 31, 2017. The next scheduled redetermination date is October 1, 2018.

The Company must comply with certain financial and non-financial covenants under the terms of the Credit Agreement and was in compliance with all such covenants as of March 31, 2018, and through the filing of this report.

Interest and commitment fees are accrued based on a borrowing base utilization grid set forth in the Credit Agreement as presented in Note 5 - Long-Term Debt in the Company’s 2017 Form 10-K. Eurodollar loans accrue interest at the London Interbank Offered Rate, plus the applicable margin from the utilization grid, and Alternate Base Rate and swingline loans accrue interest at the prime rate, plus the applicable margin from the utilization grid. Commitment fees are accrued on the unused portion of the aggregate lender commitment amount at rates from the utilization grid and are included in interest expense in the accompanying statements of operations.

The following table presents the outstanding balance, total amount of letters of credit outstanding, and available borrowing capacity under the Credit Agreement as of April 25, 2018, March 31, 2018, and December 31, 2017:



	As of April 25, 2018		As of March 31, 2018		As of December 31, 2017
	(in thousands)
Credit facility balance ⁽¹⁾	$	—	$	—	$	—
Letters of credit ⁽²⁾	200		200		200
Available borrowing capacity	999,800		924,800		924,800
Total aggregate lender commitment amount	$	1,000,000	$	925,000	$	925,000

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⁽¹⁾	Unamortized deferred financing costs attributable to the credit facility are presented as a component of other noncurrent assets on the accompanying balance sheets and totaled $2.7 million and $3.1 million as of March 31, 2018, and December 31, 2017, respectively.


⁽²⁾	Letters of credit outstanding reduce the amount available under the credit facility on a dollar-for-dollar basis.

Senior Notes

The Company’s Senior Notes consist of 6.50% Senior Notes due 2021, 6.125% Senior Notes due 2022, 6.50% Senior Notes due 2023, 5.0% Senior Notes due 2024, 5.625% Senior Notes due 2025, and 6.75% Senior Notes due 2026 (collectively referred to as “Senior Notes”). The Senior Notes, net of unamortized deferred financing costs line on the accompanying balance sheets as of March 31, 2018, and December 31, 2017, consisted of the following:



	As of March 31, 2018						As of December 31, 2017
	Principal Amount		Unamortized Deferred Financing Costs		Senior Notes, Net of Unamortized Deferred Financing Costs		Principal Amount		Unamortized Deferred Financing Costs		Senior Notes, Net of Unamortized Deferred Financing Costs
	(in thousands)
6.50% Senior Notes due 2021	$	344,611	$	2,483	$	342,128	$	344,611	$	2,656	$	341,955
6.125% Senior Notes due 2022	561,796		5,505		556,291		561,796		5,800		555,996
6.50% Senior Notes due 2023	394,985		3,525		391,460		394,985		3,707		391,278
5.0% Senior Notes due 2024	500,000		5,380		494,620		500,000		5,610		494,390
5.625% Senior Notes due 2025	500,000		6,487		493,513		500,000		6,714		493,286
6.75% Senior Notes due 2026	500,000		7,033		492,967		500,000		7,242		492,758
Total	$	2,801,392	$	30,413	$	2,770,979	$	2,801,392	$	31,729	$	2,769,663

The Senior Notes are unsecured senior obligations and rank equal in right of payment with all of the Company’s existing and any future unsecured senior debt, and are senior in right of payment to any future subordinated debt. There are no subsidiary guarantors of the Senior Notes. The Company is subject to certain covenants under the indentures governing the Senior Notes and was in compliance with all such covenants as of March 31, 2018, and through the filing of this report. The Company may redeem some or all of its Senior Notes prior to their maturity at redemption prices based on a premium, plus accrued and unpaid interest as described in the indentures governing the Senior Notes.

Senior Convertible Notes

The Company’s Senior Convertible Notes consist of $172.5 million in aggregate principal amount of 1.50% Senior Convertible Notes due July 1, 2021 (the “Senior Convertible Notes”). The Senior Convertible Notes are unsecured senior obligations and rank equal in right of payment with all of the Company’s existing and any future unsecured senior debt, and are senior in right of payment to any future subordinated debt. Please refer to Note 5 - Long-Term Debt in the Company’s 2017 Form 10-K for additional detail on the Company’s Senior Convertible Notes and associated capped call transactions.

The Senior Convertible Notes were not convertible at the option of holders as of March 31, 2018, or through the filing of this report. Notwithstanding the inability to convert, the if-converted value of the Senior Convertible Notes as of March 31, 2018, did not exceed the principal amount. The debt discount and debt-related issuance costs are amortized to the principal value of the Senior Convertible Notes as interest expense through the maturity date of July 1, 2021. Interest expense recognized on the Senior Convertible Notes related to the stated interest rate and amortization of the debt discount totaled $2.6 million and $2.4 million for the three months ended March 31, 2018, and 2017, respectively.

There have been no changes to the initial net carrying amount of the equity component of the Senior Convertible Notes recorded in additional paid-in capital on the accompanying balance sheets. The net carrying amount of the liability component of the Senior Convertible Notes, as reflected on the accompanying balance sheets as of March 31, 2018, and December 31, 2017, consisted of the following:



	As of March 31, 2018			As of December 31, 2017
	(in thousands)
Principal amount of Senior Convertible Notes	$	172,500		$	172,500
Unamortized debt discount	(28,251		)	(30,183		)
Unamortized deferred financing costs	(2,980		)	(3,210		)
Net carrying amount	$	141,269		$	139,107

The Company is subject to certain covenants under the indenture governing the Senior Convertible Notes and was in compliance with all such covenants as of March 31, 2018, and through the filing of this report.