Related Party Transactions - Schedule of Other Related Party Balances (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Related Party Transactions [Abstract]
Accounts receivable	$ 28.7	$ 23.8
Prepaid expenses	14.9	11.9
Accounts payable	8.9	11.6
Deferred revenue	2.6	13.9
Accrued liabilities	15.7	7.2
Debt payable	2,090.7	1,844.0
Lease liability (4)	25.1	24.3
Accrued interest, related parties	14.3	6.6
Other accrued liabilities, related parties	1.4	0.6
Unamortized debt issuance costs	$ 3.3	$ 2.9

Accrued interest related parties current.

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Carrying value as of the balance sheet date of obligations incurred and payable to related parties, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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The carrying amount of consideration received or receivable from related parties as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

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Other accrued liabilities related parties current.

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Prepaid expenses and other current assets related parties.

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Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

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

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The amount for notes payable (written promise to pay), payable to related parties, which are due after one year (or one business cycle).

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