Indebtedness - Schedule of Debt (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Unused Borrowing Capacity	$ 40,726	$ 12,171
Long term debt, Current	12,573	4,722
Long term debt, Noncurrent	802,900	530,042
Long term debt	815,473	534,764
Recourse debt, Total	$ 244,000	197,000
Line of Credit \| Minimum \| Basis point
Debt Instrument [Line Items]
Interest Rate	2.93%
Line of Credit \| Maximum \| Basis point
Debt Instrument [Line Items]
Interest Rate	3.06%
Notes Payable
Debt Instrument [Line Items]
Maturity Date	Dec. 31, 2018
Bank Line of Credit
Debt Instrument [Line Items]
Recourse debt, Long Term	$ 244,000	197,000
Recourse debt, Total	244,000	197,000
Recourse Debt
Debt Instrument [Line Items]
Unused Borrowing Capacity	3,406	6,571
Long term debt, Noncurrent	244,000	197,000
Long term debt	244,000	197,000
Recourse Debt \| Bank Line of Credit
Debt Instrument [Line Items]
Unused Borrowing Capacity	$ 3,406	$ 6,571
Maturity Date	Apr. 30, 2018	Apr. 30, 2018
Recourse Debt \| Bank Line of Credit \| Base Rate
Debt Instrument [Line Items]
Interest Rate		3.67%
Annual Contractual Interest Rate	2.25%	2.25%
Recourse Debt \| Bank Line of Credit \| Basis point
Debt Instrument [Line Items]
Annual Contractual Interest Rate	3.25%	3.25%
Recourse Debt \| Bank Line of Credit \| Minimum \| Base Rate
Debt Instrument [Line Items]
Interest Rate	3.70%
Recourse Debt \| Bank Line of Credit \| Maximum \| Base Rate
Debt Instrument [Line Items]
Interest Rate	5.75%
Non Recourse Debt
Debt Instrument [Line Items]
Unused Borrowing Capacity	$ 37,320	$ 5,600
Long term debt, Current	12,573	4,722
Long term debt, Noncurrent	558,900	333,042
Long term debt	571,473	337,764
Non Recourse Debt \| Line of Credit
Debt Instrument [Line Items]
Unused Borrowing Capacity	$ 27,600
Maturity Date	Dec. 31, 2020
Long term debt, Noncurrent	$ 162,800
Long term debt	$ 162,800
Non Recourse Debt \| Line of Credit \| Basis point
Debt Instrument [Line Items]
Annual Contractual Interest Rate	2.50%
Non Recourse Debt \| Term Loan A
Debt Instrument [Line Items]
Unused Borrowing Capacity	$ 5,000	$ 5,600
Maturity Date	Dec. 31, 2021	Dec. 31, 2021
Long term debt, Current	$ 672	$ 589
Long term debt, Noncurrent	147,449	146,625
Long term debt	$ 148,121	$ 147,214
Non Recourse Debt \| Term Loan A \| Basis point
Debt Instrument [Line Items]
Interest Rate		3.07%
Annual Contractual Interest Rate	2.75%	2.75%
Non Recourse Debt \| Term Loan A \| Minimum \| Basis point
Debt Instrument [Line Items]
Interest Rate	3.04%
Non Recourse Debt \| Term Loan A \| Maximum \| Basis point
Debt Instrument [Line Items]
Interest Rate	3.21%
Non Recourse Debt \| Term Loan and Term Loan B
Debt Instrument [Line Items]
Long term debt, Current	$ 117
Long term debt, Noncurrent	43,137
Long term debt	$ 43,254
Non Recourse Debt \| Term Loan and Term Loan B \| Basis point
Debt Instrument [Line Items]
Interest Rate	6.00%
Annual Contractual Interest Rate	5.00%
Non Recourse Debt \| Term Loan B
Debt Instrument [Line Items]
Maturity Date		Dec. 31, 2021
Long term debt, Current		$ 116
Long term debt, Noncurrent		22,014
Long term debt		$ 22,130
Non Recourse Debt \| Term Loan B \| Basis point
Debt Instrument [Line Items]
Interest Rate		6.00%
Annual Contractual Interest Rate		5.00%
Non Recourse Debt \| Bank term loan due in September 2022
Debt Instrument [Line Items]
Interest Rate	2.71%
Maturity Date	Sep. 30, 2022
Long term debt, Current	$ 1,050
Long term debt, Noncurrent	21,917
Long term debt	$ 22,967
Non Recourse Debt \| Bank term loan due in September 2022 \| Basis point
Debt Instrument [Line Items]
Annual Contractual Interest Rate	2.25%
Non Recourse Debt \| Bank term loan due in April 2022
Debt Instrument [Line Items]
Interest Rate	4.50%	6.25%
Maturity Date	Apr. 30, 2022	Apr. 30, 2022
Long term debt, Current	$ 1,289	$ 1,159
Long term debt, Noncurrent	27,440	29,580
Long term debt	$ 28,729	$ 30,739
Non Recourse Debt \| Bank term loan due in April 2022 \| Basis point
Debt Instrument [Line Items]
Interest Rate	4.50%
Non Recourse Debt \| Solar Asset Backed Securities Class A
Debt Instrument [Line Items]
Interest Rate	4.40%	4.40%
Maturity Date	Jul. 31, 2024	Jul. 31, 2024
Long term debt, Current	$ 3,670	$ 2,858
Long term debt, Noncurrent	98,929	102,042
Long term debt	102,599	$ 104,900
Non Recourse Debt \| Bank term loan due in July 2021
Debt Instrument [Line Items]
Unused Borrowing Capacity	$ 4,720
Maturity Date	Jul. 31, 2021
Long term debt, Current	$ 5,775
Long term debt, Noncurrent	21,575
Long term debt	$ 27,350
Non Recourse Debt \| Bank term loan due in July 2021 \| Minimum
Debt Instrument [Line Items]
Interest Rate	6.25%
Non Recourse Debt \| Bank term loan due in July 2021 \| Maximum
Debt Instrument [Line Items]
Interest Rate	9.75%
Non Recourse Debt \| Notes Payable
Debt Instrument [Line Items]
Interest Rate	12.00%	12.00%
Maturity Date	Dec. 31, 2018	Dec. 31, 2018
Long term debt, Noncurrent	$ 35,653	$ 32,781
Long term debt	$ 35,653	$ 32,781
Non Recourse Debt \| Year One \| Term Loan and Term Loan B
Debt Instrument [Line Items]
Maturity Date	Dec. 31, 2020
Non Recourse Debt \| Solar Asset Backed Securities Class B
Debt Instrument [Line Items]
Interest Rate	5.38%	5.38%
Maturity Date	Jul. 31, 2024	Jul. 31, 2024

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

No definition available.

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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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No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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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The carrying value as of the balance sheet date of the noncurrent portion 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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-Publisher FASB
-Name Accounting Standards Codification
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