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- Definition

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt discount.

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- Definition

Amount, after accumulated amortization, of debt premium.

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- Definition

Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Credit Facilities and Debt - Borrowing Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2017	Dec. 22, 2016	Jun. 21, 2016	Dec. 31, 2014	Oct. 22, 2012	Aug. 14, 2012	Oct. 24, 2011
Debt Instrument [Line Items]
Loss on extinguishment of debt	$ 910	$ (348)	$ 18,565
Debt Issuance Costs, Noncurrent, Net	511	843
5.625% Senior Notes due 2026 [Member]
Debt Instrument [Line Items]
5.375% Senior Notes due 2020	$ 495,518	$ 494,915			$ 500,000
Convertible debentures, interest rate	5.625%	5.625%
Debt Instrument, Unamortized Premium	$ 0	$ 0
Unamortized Debt Issuance Expense	$ 4,500	$ 5,100
Debt Instrument, Interest Rate, Effective Percentage	5.625%	5.625%
nuan_DebtInstrumentMaturityYear	2026	2026
6.0% Senior Notes due 2024 [Member]
Debt Instrument [Line Items]
5.375% Senior Notes due 2020	$ 298,529	$ 298,220				$ 300,000
Convertible debentures, interest rate	6.00%	6.00%
Debt Instrument, Unamortized Premium	$ 0	$ 0
Unamortized Debt Issuance Expense	$ 1,500	$ 1,800
Debt Instrument, Interest Rate, Effective Percentage	6.00%	6.00%
nuan_DebtInstrumentMaturityYear	2024	2024
5.375% Senior Notes due August 15, 2020
Debt Instrument [Line Items]
5.375% Senior Notes due 2020	$ 0	$ 298,759						$ 350,000	$ 700,000
Convertible debentures, interest rate	5.375%	5.375%						5.375%
Debt Instrument, Unamortized Premium	$ 0	$ 0
Unamortized Debt Issuance Expense	$ 0	$ 1,200
Debt Instrument, Interest Rate, Effective Percentage	5.375%	5.375%
nuan_DebtInstrumentMaturityYear	2020	2020
Loss on extinguishment of debt	$ (300)	$ (18,600)
2.75% Convertible Debentures due November 1, 2031
Debt Instrument [Line Items]
Convertible debentures, interest rate	2.75%	2.75%					2.75%			2.75%
Unamortized Debt Issuance Expense	$ 0	$ 0
Debt Instrument, Interest Rate, Effective Percentage	7.432%	7.432%
nuan_DebtInstrumentMaturityYear	2031	2031
Loss on extinguishment of debt			$ (17,700)
Debt Instrument, Unamortized Discount	$ 0	$ 0
2.75% Convertible Debentures, net of unamortized discount	46,568	46,568
1.25% Convertible Debentures due 2025 [Member]
Debt Instrument [Line Items]
2.75% Convertible Debentures, net of unamortized discount	$ 275,257	$ 263,863
Convertible Debentures One Point Five Percent Due November One Twenty Thirty Five [Member] [Member]
Debt Instrument [Line Items]
Convertible debentures, interest rate	1.50%	1.50%
Unamortized Debt Issuance Expense	$ 800	$ 1,100
Debt Instrument, Interest Rate, Effective Percentage	5.394%	5.394%
nuan_DebtInstrumentMaturityYear	2035	2035
Debt Instrument, Unamortized Discount	$ 22,700	$ 32,800
2.75% Convertible Debentures, net of unamortized discount	240,406	229,906
Convertible Debentures One Percent Due Twenty Thirty Five [Member]
Debt Instrument [Line Items]
5.375% Senior Notes due 2020	580,639	$ 553,973
Convertible debentures, interest rate		1.00%		1.00%
Unamortized Debt Issuance Expense	$ 4,300	$ 5,600
Debt Instrument, Interest Rate, Effective Percentage	5.622%	5.622%
nuan_DebtInstrumentMaturityYear	2035	2035
Loss on extinguishment of debt		$ (2,400)
Debt Instrument, Unamortized Discount	$ 91,600	$ 116,900
Convertible Debentures 1.25% Due 2025 [Member]
Debt Instrument [Line Items]
Convertible debentures, interest rate	1.25%	1.25%
Unamortized Debt Issuance Expense	$ 3,100	$ 3,700
Debt Instrument, Interest Rate, Effective Percentage	5.578%	5.578%
nuan_DebtInstrumentMaturityYear	2025	2025
Debt Instrument, Unamortized Discount	$ 71,600	$ 82,400
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	$ 0	$ 0