Debt - Debt Outstanding (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Term loan	$ 788,000	$ 794,000
Unamortized discount	(7,192)	(3,499)
Unamortized debt issuance expense	(3,032)	(7,612)
Revolver	455,919	270,559
Total Senior Credit Facility	1,233,695	1,053,448
Capital Lease Obligations	6,412	7,431
Other debt	2,604	2,728
Total debt	2,730,616	2,581,887
Current portion of capital lease obligations, long-term debt and non-recourse debt	(340,143)	(28,920)
Capital Lease Obligations, long-term portion	(4,954)	(6,059)
Non-Recourse Debt, long-term portion	(22,201)	(365,364)
Long-Term Debt	2,363,318	2,181,544
Non-Recourse Debt
Debt Instrument [Line Items]
Unamortized discount	(186)	(271)
Unamortized debt issuance expense	(5,159)	(9,322)
Non-Recourse Debt	357,692	394,008
Total Non-Recourse Debt	352,347	384,415
6.00% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Unamortized debt issuance expense	(4,950)	(5,325)
Long-term Debt, Gross	350,000	350,000
Long-term Debt	$ 345,050	344,675
Interest rate	6.00%
5.875% Senior Notes, due 2024 \| Senior Notes
Debt Instrument [Line Items]
Unamortized debt issuance expense	$ (3,078)	(3,385)
Long-term Debt, Gross	250,000	250,000
Long-term Debt	$ 246,922	246,615
Interest rate	5.875%
5.125% Senior Notes, due 2023 \| Senior Notes
Debt Instrument [Line Items]
Unamortized debt issuance expense	$ (3,712)	(4,184)
Long-term Debt, Gross	300,000	300,000
Long-term Debt	$ 296,288	295,816
Interest rate	5.125%
5.875% Senior Notes due 2022 \| Senior Notes
Debt Instrument [Line Items]
Unamortized debt issuance expense	$ (2,702)	(3,241)
Long-term Debt, Gross	250,000	250,000
Long-term Debt	$ 247,298	$ 246,759
Interest rate	5.875%

Long term debt, nonrecourse debt and capital lease obligation including current portion, net of discount.

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Non-recourse debt, excluding premium discount.

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Noncurrent portion of non-recourse debt .

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- Definition

Total senior credit facility.

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Term loans.

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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.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

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

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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.

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Amount, after accumulated amortization, of debt discount.

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- Definition

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 carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of debt for which creditor does not have general recourse to the debtor but rather has recourse only to the property used for collateral in the transaction or other specific property.

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Amount of long-term debt classified as other.

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