Debt (Tables)

9 Months Ended

Jun. 30, 2021

Debt Disclosure [Abstract]

Borrowing Obligations and Applicable Margin for Borrowings

As of June 30, 2021 and September 30, 2020, we had the following borrowing obligations (dollars in thousands): 

	June 30, 2021		September 30, 2020
5.625% Senior Notes due 2026, net of deferred issuance costs of $3.4 million and $3.9 million, respectively. Effective interest rate 5.625%.	$	496,610	$	496,148
1.000% Convertible Debentures due 2035, net of unamortized discount of $14.2 million and $64.8 million, respectively, and deferred issuance costs of $0.6 million and $2.9 million, respectively. Effective interest rate 5.622%.	204,719		608,767
1.250% Convertible Debentures due 2025, net of unamortized discount of $38.4 million and $45.2 million, respectively, and deferred issuance costs of $1.6 million and $1.9 million, respectively. Effective interest rate 5.578%.	222,664		215,582
1.500% Convertible Debentures due 2035, net of unamortized discount of $0.6 million and $10.4 million, respectively, and deferred issuance costs of $0.3 million as of September 30, 2020. Effective interest rate 5.394%.	43,480		216,627
Deferred issuance costs related to our Revolving Credit Facility	(1,945)		(451)
Total debt	965,528		1,536,673
Less: current portion (a)	(470,863)		(432,209)
Total long-term debt	$	494,665	$	1,104,464

__________

(a) As of June 30, 2021, the holders have the right to convert all or any portion of the 1.25% 2025 Debentures, 1.5% 2035 Debentures, and 1.0% 2035 Debentures between July 1, 2021 and September 30, 2021. Additionally, the holders of the 1.5% 2035 Debentures will have the right to redeem the notes in November 2021. As a result, the net carrying amounts of the convertible debentures were included in current liabilities as of June 30, 2021.

Schedule of Maturities of Long-term Debt

The following table summarizes the maturities of our borrowing obligations as of June 30, 2021 (dollars in thousands):

Fiscal Year	Convertible Debentures (a)		Senior Notes		Total
2021	$	526,325	$	—	$	526,325
2022	—		—		—
2023	—		—		—
2024	—		—		—
2025	—		—		—
Thereafter	—		500,000		500,000
Total before unamortized discount	526,325		500,000		1,026,325
Less: unamortized discount and issuance costs	(55,462)		(5,335)		(60,797)
Total debt	$	470,863	$	494,665	$	965,528

__________

(a) As more fully described below, as of June 30, 2021, the holders have the right to convert all or any portion of the 1.25% 2025 Debentures, 1.5% 2035 Debentures, and 1.0% 2035 Debentures between July 1, 2021 and September 30, 2021. Additionally, the holders of the 1.5% 2035 Debentures will have the right to redeem the notes in November 2021. As a result, these convertible debentures were treated as if they were due in fiscal year 2021.