Revenue Recognition Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2019	Mar. 31, 2019	Oct. 01, 2018
Revenue Recognition [Abstract]
Contract with Customer, Asset, Net, Current	$ 59,800	$ 59,800
Deferred Costs, Current	13,400	13,400
Contract with Customer, Liability	715,183	715,183	$ 693,272
Capitalized Contract Cost, Net	17,700	17,700
Hardware revenue	7,100	17,200
Capitalized Contract Cost, Net, Noncurrent	27,800	27,800
Capitalized Contract Cost, Amortization	3,700	7,200
Deferred Costs, Noncurrent	96,200	96,200
Contract with Customer, Asset, Net, Noncurrent	$ 100,800	$ 100,800

Hardware revenue

No definition available.

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- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as current.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as noncurrent.

+ References

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

+ References

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- Definition

+ References

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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- Definition

Amount of deferred cost, excluding capitalized cost related to contract with customer; classified as noncurrent.

+ References

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

Sum of the carrying amounts as of the balance sheet date of deferred costs capitalized at the end of the reporting period that are expected to be charged against earnings within one year or the normal operating cycle, if longer.

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- References

No definition available.

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