Consolidating Financial Information of Guarantors and Issuers (Income Statement) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 25, 2018	Dec. 31, 2017
Condensed Financial Statements, Captions [Line Items]
Net revenues	$ 66,977	$ 54,727
Costs and expenses:
Cost of food, merchandise, and games revenues	7,649	6,003
Operating expenses	98,205	88,828
Selling, general and administrative	31,666	28,682
Depreciation and amortization	13,589	5,521
Loss on impairment / retirement of fixed assets, net	1,424	1,340
Gain on sale of investment	(617)	0
Total costs and expenses	151,916	130,374
Operating loss	(84,939)	(75,647)
Interest (income) expense, net	20,687	19,536
Net effect of swaps	6,379	(3,628)
Loss on early debt extinguishment	0	1,073	$ 23,100
(Gain) loss on foreign currency	(8,669)	10,094
Other (income) expense	322	(123)
(Income) loss from investment in affiliates	0	0
Loss before taxes	(103,658)	(102,599)
Provision for taxes	(19,985)	(19,199)
Net loss	(83,673)	(83,400)
Other comprehensive income (loss), (net of tax):
Foreign currency translation adjustment	(3,050)	4,604
Cash flow hedging derivative activity		2,018
Other comprehensive income (loss), (net of tax)	(3,050)	6,622
Total comprehensive loss	(86,723)	(76,778)
June 2014 Notes [Member] | Reportable Legal Entities [Member] | Cedar Fair L.P. (Parent) [Member]
Condensed Financial Statements, Captions [Line Items]
Net revenues	(15,642)	(10,767)
Costs and expenses:
Cost of food, merchandise, and games revenues	0	0
Operating expenses	0	0
Selling, general and administrative	1,439	759
Depreciation and amortization	0	0
Loss on impairment / retirement of fixed assets, net	0	0
Gain on sale of investment	0
Total costs and expenses	1,439	759
Operating loss	(17,081)	(11,526)
Interest (income) expense, net	6,391	4,904
Net effect of swaps	991	(2,207)
Loss on early debt extinguishment		0
(Gain) loss on foreign currency	0	0
Other (income) expense	59	59
(Income) loss from investment in affiliates	58,449	68,528
Loss before taxes	(82,971)	(82,810)
Provision for taxes	702	590
Net loss	(83,673)	(83,400)
Other comprehensive income (loss), (net of tax):
Foreign currency translation adjustment	(3,050)	4,604
Cash flow hedging derivative activity		2,018
Other comprehensive income (loss), (net of tax)	(3,050)	6,622
Total comprehensive loss	(86,723)	(76,778)
June 2014 Notes [Member] | Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net revenues	59,905	49,787
Costs and expenses:
Cost of food, merchandise, and games revenues	7,597	6,003
Operating expenses	25,189	25,859
Selling, general and administrative	14,657	12,793
Depreciation and amortization	13,581	5,513
Loss on impairment / retirement of fixed assets, net	1,414	1,300
Gain on sale of investment	0
Total costs and expenses	62,438	51,468
Operating loss	(2,533)	(1,681)
Interest (income) expense, net	3,553	4,682
Net effect of swaps	0	0
Loss on early debt extinguishment		886
(Gain) loss on foreign currency	0	0
Other (income) expense	10,670	8,768
(Income) loss from investment in affiliates	6,190	20,585
Loss before taxes	(22,946)	(36,602)
Provision for taxes	(3,689)	(3,876)
Net loss	(19,257)	(32,726)
Other comprehensive income (loss), (net of tax):
Foreign currency translation adjustment	0	0
Cash flow hedging derivative activity		0
Other comprehensive income (loss), (net of tax)	0	0
Total comprehensive loss	(19,257)	(32,726)
June 2014 Notes [Member] | Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net revenues	19,133	14,582
Costs and expenses:
Cost of food, merchandise, and games revenues	0	0
Operating expenses	19,133	14,582
Selling, general and administrative	0	0
Depreciation and amortization	0	0
Loss on impairment / retirement of fixed assets, net	0	0
Gain on sale of investment	0
Total costs and expenses	19,133	14,582
Operating loss	0	0
Interest (income) expense, net	0	0
Net effect of swaps	0	0
Loss on early debt extinguishment		0
(Gain) loss on foreign currency	0	0
Other (income) expense	0	0
(Income) loss from investment in affiliates	(83,901)	(121,841)
Loss before taxes	83,901	121,841
Provision for taxes	0	0
Net loss	83,901	121,841
Other comprehensive income (loss), (net of tax):
Foreign currency translation adjustment	3,050	(4,604)
Cash flow hedging derivative activity		(630)
Other comprehensive income (loss), (net of tax)	3,050	(5,234)
Total comprehensive loss	86,951	116,607
April 2017 Notes [Member] | Reportable Legal Entities [Member] | Cedar Fair L.P. (Parent) [Member]
Condensed Financial Statements, Captions [Line Items]
Net revenues	(15,642)	(10,767)
Costs and expenses:
Cost of food, merchandise, and games revenues	0	0
Operating expenses	0	0
Selling, general and administrative	1,439	759
Depreciation and amortization	0	0
Loss on impairment / retirement of fixed assets, net	0	0
Gain on sale of investment	0
Total costs and expenses	1,439	759
Operating loss	(17,081)	(11,526)
Interest (income) expense, net	6,391	4,904
Net effect of swaps	991	(2,207)
Loss on early debt extinguishment		0
(Gain) loss on foreign currency	0	0
Other (income) expense	59	59
(Income) loss from investment in affiliates	58,449	68,528
Loss before taxes	(82,971)	(82,810)
Provision for taxes	702	590
Net loss	(83,673)	(83,400)
Other comprehensive income (loss), (net of tax):
Foreign currency translation adjustment	(3,050)	4,604
Cash flow hedging derivative activity		2,018
Other comprehensive income (loss), (net of tax)	(3,050)	6,622
Total comprehensive loss	(86,723)	(76,778)
April 2017 Notes [Member] | Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net revenues	8,717	1,706
Costs and expenses:
Cost of food, merchandise, and games revenues	356	104
Operating expenses	9,037	8,889
Selling, general and administrative	1,095	1,150
Depreciation and amortization	13,581	5,513
Loss on impairment / retirement of fixed assets, net	1,028	649
Gain on sale of investment	0
Total costs and expenses	25,097	16,305
Operating loss	(16,380)	(14,599)
Interest (income) expense, net	(9,831)	(6,871)
Net effect of swaps	0	0
Loss on early debt extinguishment		0
(Gain) loss on foreign currency	0	0
Other (income) expense	10,670	8,768
(Income) loss from investment in affiliates	6,190	20,585
Loss before taxes	(23,409)	(37,081)
Provision for taxes	(4,152)	(4,355)
Net loss	(19,257)	(32,726)
Other comprehensive income (loss), (net of tax):
Foreign currency translation adjustment	0	0
Cash flow hedging derivative activity		0
Other comprehensive income (loss), (net of tax)	0	0
Total comprehensive loss	(19,257)	(32,726)
April 2017 Notes [Member] | Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net revenues	5,734	8,932
Costs and expenses:
Cost of food, merchandise, and games revenues	0	0
Operating expenses	5,734	8,932
Selling, general and administrative	0	0
Depreciation and amortization	0	0
Loss on impairment / retirement of fixed assets, net	0	0
Gain on sale of investment	0
Total costs and expenses	5,734	8,932
Operating loss	0	0
Interest (income) expense, net	0	0
Net effect of swaps	0	0
Loss on early debt extinguishment		0
(Gain) loss on foreign currency	0	0
Other (income) expense	0	0
(Income) loss from investment in affiliates	(83,901)	(121,841)
Loss before taxes	83,901	121,841
Provision for taxes	0	0
Net loss	83,901	121,841
Other comprehensive income (loss), (net of tax):
Foreign currency translation adjustment	3,050	(4,604)
Cash flow hedging derivative activity		(630)
Other comprehensive income (loss), (net of tax)	3,050	(5,234)
Total comprehensive loss	86,951	116,607
Co-Issuer Subsidiary (Magnum) [Member] | June 2014 Notes [Member] | Reportable Legal Entities [Member] | Subsidiary Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Net revenues	3,285	854
Costs and expenses:
Cost of food, merchandise, and games revenues	0	0
Operating expenses	48,172	42,671
Selling, general and administrative	14,552	14,450
Depreciation and amortization	8	8
Loss on impairment / retirement of fixed assets, net	0	0
Gain on sale of investment	(617)
Total costs and expenses	62,115	57,129
Operating loss	(58,830)	(56,275)
Interest (income) expense, net	5,030	4,367
Net effect of swaps	5,388	(1,421)
Loss on early debt extinguishment		187
(Gain) loss on foreign currency	(11)	(41)
Other (income) expense	(11,506)	(9,804)
(Income) loss from investment in affiliates	14,659	28,815
Loss before taxes	(72,390)	(78,378)
Provision for taxes	(13,939)	(9,851)
Net loss	(58,451)	(68,527)
Other comprehensive income (loss), (net of tax):
Foreign currency translation adjustment	0	0
Cash flow hedging derivative activity		630
Other comprehensive income (loss), (net of tax)	0	630
Total comprehensive loss	(58,451)	(67,897)
Co-Issuer Subsidiary (Magnum) [Member] | April 2017 Notes [Member] | Reportable Legal Entities [Member] | Subsidiary Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Net revenues	3,285	854
Costs and expenses:
Cost of food, merchandise, and games revenues	0	0
Operating expenses	48,172	42,671
Selling, general and administrative	14,552	14,450
Depreciation and amortization	8	8
Loss on impairment / retirement of fixed assets, net	0	0
Gain on sale of investment	(617)
Total costs and expenses	62,115	57,129
Operating loss	(58,830)	(56,275)
Interest (income) expense, net	5,030	4,367
Net effect of swaps	5,388	(1,421)
Loss on early debt extinguishment		187
(Gain) loss on foreign currency	(11)	(41)
Other (income) expense	(11,506)	(9,804)
(Income) loss from investment in affiliates	14,659	28,815
Loss before taxes	(72,390)	(78,378)
Provision for taxes	(13,939)	(9,851)
Net loss	(58,451)	(68,527)
Other comprehensive income (loss), (net of tax):
Foreign currency translation adjustment	0	0
Cash flow hedging derivative activity		630
Other comprehensive income (loss), (net of tax)	0	630
Total comprehensive loss	(58,451)	(67,897)
Co-Issuer Subsidiary (Cedar Canada) [Member] | June 2014 Notes [Member] | Reportable Legal Entities [Member] | Subsidiary Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Net revenues	296	271
Costs and expenses:
Cost of food, merchandise, and games revenues	52	0
Operating expenses	5,711	5,716
Selling, general and administrative	1,018	680
Depreciation and amortization	0	0
Loss on impairment / retirement of fixed assets, net	10	40
Gain on sale of investment	0
Total costs and expenses	6,791	6,436
Operating loss	(6,495)	(6,165)
Interest (income) expense, net	5,713	5,583
Net effect of swaps	0	0
Loss on early debt extinguishment		0
(Gain) loss on foreign currency	(8,658)	10,135
Other (income) expense	1,099	854
(Income) loss from investment in affiliates	4,603	3,913
Loss before taxes	(9,252)	(26,650)
Provision for taxes	(3,059)	(6,062)
Net loss	(6,193)	(20,588)
Other comprehensive income (loss), (net of tax):
Foreign currency translation adjustment	(3,050)	4,604
Cash flow hedging derivative activity		0
Other comprehensive income (loss), (net of tax)	(3,050)	4,604
Total comprehensive loss	(9,243)	(15,984)
Co-Issuer Subsidiary (Cedar Canada) [Member] | April 2017 Notes [Member] | Reportable Legal Entities [Member] | Subsidiary Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Net revenues	296	271
Costs and expenses:
Cost of food, merchandise, and games revenues	52	0
Operating expenses	5,711	5,716
Selling, general and administrative	1,018	680
Depreciation and amortization	0	0
Loss on impairment / retirement of fixed assets, net	10	40
Gain on sale of investment	0
Total costs and expenses	6,791	6,436
Operating loss	(6,495)	(6,165)
Interest (income) expense, net	5,713	5,583
Net effect of swaps	0	0
Loss on early debt extinguishment		0
(Gain) loss on foreign currency	(8,658)	10,135
Other (income) expense	1,099	854
(Income) loss from investment in affiliates	4,603	3,913
Loss before taxes	(9,252)	(26,650)
Provision for taxes	(3,059)	(6,062)
Net loss	(6,193)	(20,588)
Other comprehensive income (loss), (net of tax):
Foreign currency translation adjustment	(3,050)	4,604
Cash flow hedging derivative activity		0
Other comprehensive income (loss), (net of tax)	(3,050)	4,604
Total comprehensive loss	(9,243)	(15,984)
Co-Issuer Subsidiary (Millennium) [Member] | April 2017 Notes [Member] | Reportable Legal Entities [Member] | Subsidiary Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Net revenues	64,587	53,731
Costs and expenses:
Cost of food, merchandise, and games revenues	7,241	5,899
Operating expenses	29,551	22,620
Selling, general and administrative	13,562	11,643
Depreciation and amortization	0	0
Loss on impairment / retirement of fixed assets, net	386	651
Gain on sale of investment	0
Total costs and expenses	50,740	40,813
Operating loss	13,847	12,918
Interest (income) expense, net	13,384	11,553
Net effect of swaps	0	0
Loss on early debt extinguishment		886
(Gain) loss on foreign currency	0	0
Other (income) expense	0	0
(Income) loss from investment in affiliates	0	0
Loss before taxes	463	479
Provision for taxes	463	479
Net loss	0	0
Other comprehensive income (loss), (net of tax):
Foreign currency translation adjustment	0	0
Cash flow hedging derivative activity		0
Other comprehensive income (loss), (net of tax)	0	0
Total comprehensive loss	$ 0	$ 0