Leasing (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 30, 2018	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Leasing [Line Items]
Capital leases, maximum term		20 years
Solar power systems leased and to be leased [Abstract]
Solar power systems leased	$ 139,343,000	$ 139,343,000	$ 749,697,000
Solar power systems to be leased	12,158,000	12,158,000	26,830,000
Solar power systems leased and to be leased, gross	151,501,000	151,501,000	776,527,000
Less: accumulated depreciation and impairment	(58,944,000)	(58,944,000)	(407,309,000)
Solar power systems leased and to be leased, net	92,557,000	92,557,000	369,218,000
Pledged solar assets, book value	0	0	112,400,000
Operating lease, impairment loss		74,900,000
Operating Leases, Future Minimum Payments Receivable [Abstract]
Fiscal 2019	1,224,000	1,224,000
Fiscal 2020	1,186,000	1,186,000
Fiscal 2021	1,189,000	1,189,000
Fiscal 2022	1,193,000	1,193,000
Fiscal 2023	1,197,000	1,197,000
Thereafter	18,359,000	18,359,000
Total	24,348,000	24,348,000
Financing receivables:
Minimum lease payments receivable	43,939,000	43,939,000	690,249,000
Unguaranteed residual value	4,450,000	4,450,000	73,344,000
Unearned income	(8,859,000)	(8,859,000)	(115,854,000)
Allowance for estimated losses	(18,656,000)	(18,656,000)	(297,972,000)
Net financing receivables, held for sale	20,874,000	20,874,000	349,767,000
Net financing receivables - current, held for sale	1,282,000	1,282,000	19,095,000
Net financing receivables - non-current held for sale	19,592,000	19,592,000	330,672,000
Pledged financing receivables	0	0	113,400,000
Allowance for doubtful accounts	0	0	6,100,000
Capital Leases, Future Minimum Payments Receivable, Fiscal Year Maturity [Abstract]
Fiscal 2019	2,126,000	2,126,000
Fiscal 2020	2,129,000	2,129,000
Fiscal 2021	2,137,000	2,137,000
Fiscal 2022	2,146,000	2,146,000
Fiscal 2023	2,155,000	2,155,000
Thereafter	33,246,000	33,246,000
Total	$ 43,939,000	43,939,000
Impairment of residential lease assets		251,984,000	624,335,000	$ (7,263,000)
Net impairment charges attributable to stockholders		180,100,000	473,700,000
Sale-Leaseback [Abstract]
Sale leaseback transaction, lease term	25 years
Sale leaseback, residential customers lease term	25 years
Future minimum lease obligations	$ 65,900,000	$ 65,900,000
Operating lease, term	25 years	25 years
Sale leaseback, minimum lease obligation	$ 509,900,000	$ 509,900,000
Net financing proceeds		32,300,000	259,600,000
Long-term sale-leaseback financing	$ 583,418,000	583,418,000	479,597,000
Residential leases
Capital Leases, Future Minimum Payments Receivable, Fiscal Year Maturity [Abstract]
Impairment of residential lease assets		$ 189,700,000
Maximum
Sale-Leaseback [Abstract]
Sale leaseback transaction, lease term	30 years
Noncontrolling Interest
Capital Leases, Future Minimum Payments Receivable, Fiscal Year Maturity [Abstract]
Net gain allocated to noncontrolling interest - leasing operations			(9,600,000)
Redeemable Noncontrolling Interest
Capital Leases, Future Minimum Payments Receivable, Fiscal Year Maturity [Abstract]
Net gain allocated to noncontrolling interest - leasing operations			$ (150,600,000)