Debt and Credit Facilities (Tables)

3 Months Ended

Dec. 31, 2018

Debt Disclosure [Abstract]

Schedule of Maturities of Long-term Debt [Table Text Block]

The following table summarizes the maturities of our borrowing obligations as of December 31, 2018 (dollars in thousands):

Fiscal Year	Convertible Debentures(1)			Senior Notes			Total
2019	$	—		$	—		$	—
2020	—			300,000			300,000
2021	—			—			—
2022	310,463			—			310,463
2023	676,488			—			676,488
Thereafter	350,000			800,000			1,150,000
Total before unamortized discount	1,336,951			1,100,000			2,436,951
Less: unamortized discount and issuance costs	(230,735		)	(8,482		)	(239,217		)
Total long-term debt	$	1,106,216		$	1,091,518		$	2,197,734

⁽¹⁾  Pursuant to the terms of each convertible instrument, holders have the right to redeem the debt on specific dates prior to maturity. The repayment schedule above assumes that payment is due on the next redemption date after December 31, 2018.

Borrowing Obligations and Applicable Margin for Borrowings

As of December 31, 2018 and September 30, 2018, we had the following borrowing obligations (dollars in thousands):

	December 31, 2018			September 30, 2018
5.625% Senior Notes due 2026, net of deferred issuance costs of $4.9 million and $5.1 million, respectively. Effective interest rate 5.625%.	$	495,056		$	494,915
5.375% Senior Notes due 2020, net of deferred issuance costs of $1.1 million and $1.2 million, respectively. Effective interest rate 5.375%.	298,925			298,759
6.000% Senior Notes due 2024, net of deferred issuance costs of $1.7 million and $1.8 million, respectively. Effective interest rate 6.000%.	298,297			298,220
1.00% Convertible Debentures due 2035, net of unamortized discount of $110.7 million and $116.9 million, respectively, and deferred issuance costs of $5.3 million and $5.6 million, respectively. Effective interest rate 5.622%.	560,507			553,973
2.75% Convertible Debentures due 2031. Effective interest rate 7.432%.	46,568			46,568
1.25% Convertible Debentures due 2025, net of unamortized discount of $79.8 million and $82.4 million, respectively, and deferred issuance costs of $3.6 million and $3.7 million, respectively. Effective interest rate 5.578%.	266,655			263,863
1.50% Convertible Debentures due 2035, net of unamortized discount of $30.4 million and $32.8 million, respectively, and deferred issuance costs of $1.0 million and $1.1 million, respectively. Effective interest rate 5.394%.	232,486			229,906
Deferred issuance costs related to our Revolving Credit Facility	(760		)	(843		)
Total debt	2,197,734			2,185,361
Less: current portion	—			—
Total long-term debt	$	2,197,734		$	2,185,361