nuan_DebtInstrumentMaturityYear

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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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.

+ Details

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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Balance Type:	debit
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- Definition

Amount, after accumulated amortization, of debt premium.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Debt and Credit Facilities Applicable Borrowing Rates and Additional Detail (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2020	Sep. 30, 2019	Sep. 30, 2020	Mar. 13, 2017	Dec. 22, 2016	Dec. 07, 2015	Jun. 01, 2015	Oct. 24, 2011
5.625% Senior Notes due 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.625%		5.625%		5.625%
Debt Instrument, Interest Rate, Effective Percentage	5.63%		5.63%
nuan_DebtInstrumentMaturityYear	2026	2026
Unamortized Debt Issuance Expense	$ 3,698		$ 3,852
Debt Instrument, Unamortized Premium	$ 0		$ 0
5.375% Senior Notes due August 15, 2020
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					5.375%
Convertible Debentures Two Point Seven Five Percent Due November One Twenty Thirty One [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage								2.75%
Convertible Debentures One Point Five Percent Due November One Twenty Thirty Five [Member] [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.50%		1.50%				1.50%
Debt Instrument, Interest Rate, Effective Percentage	5.394%		5.39%
nuan_DebtInstrumentMaturityYear	2035	2035
Unamortized Debt Issuance Expense	$ 266		$ 346
Debt Instrument, Unamortized Discount	$ 8,065		$ 10,422
Convertible Debentures One Percent Due Twenty Thirty Five [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.00%		1.00%			1.00%
Debt Instrument, Interest Rate, Effective Percentage	5.622%		5.62%
nuan_DebtInstrumentMaturityYear	2035	2035
Unamortized Debt Issuance Expense	$ 2,600		$ 2,932
Debt Instrument, Unamortized Discount	$ 57,851		$ 64,789
Convertible Debentures 1.25% Due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.25%		1.25%	1.25%
Debt Instrument, Interest Rate, Effective Percentage	5.578%		5.578%
nuan_DebtInstrumentMaturityYear	2025	2025
Unamortized Debt Issuance Expense	$ 1,818		$ 1,924
Debt Instrument, Unamortized Discount	$ 42,928		$ 45,150
Minimum \| Revolving Credit Facility Due April Fifteenth Twenty Twenty One [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Minimum \| Revolving Credit Facility Due April Fifteenth Twenty Twenty One [Member] \| London Interbank Offered Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.50%
Maximum \| Revolving Credit Facility Due April Fifteenth Twenty Twenty One [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.75%
Maximum \| Revolving Credit Facility Due April Fifteenth Twenty Twenty One [Member] \| London Interbank Offered Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.75%