Goodwill and Other Intangible Assets - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) subsidiary	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Goodwill [Line Items]
Accumulated goodwill impairment losses	$ 159,895	$ 159,895
Amortization expense for intangible assets	12,079	12,526	$ 20,430
Estimated future amortization expense, 2018	6,200
Estimated future amortization expense, 2019	3,744
Estimated future amortization expense, 2020	3,124
Estimated future amortization expense, 2021	2,877
Estimated future amortization expense, 2022	2,562
Estimated future amortization expense, thereafter	17,420
Impairments of long-lived assets	28,992	0	0
Long-lived assets	1,934,904	2,151,633
Impairments	0	23,465	0
Central America & U.S. Campuses
Goodwill [Line Items]
Accumulated goodwill impairment losses	96,754	96,754
Long-lived assets	0
Impairments	0	0	0
EMEAA
Goodwill [Line Items]
Accumulated goodwill impairment losses	63,141	63,141
Long-lived assets	0
Impairments	0	23,465	0
EMEAA | Monash South Africa (MSA)
Goodwill [Line Items]
Impairments		19,302
EMEAA | Germany
Goodwill [Line Items]
Impairments		4,163
Tradenames
Goodwill [Line Items]
Total impairments of tradenames	8,532	0	0
Tradenames | Central America & U.S. Campuses
Goodwill [Line Items]
Total impairments of tradenames	5,443	0	0
Impairment of long-lived assets to be disposed of	12,000
Tradenames | EMEAA
Goodwill [Line Items]
Total impairments of tradenames	3,089	$ 0	$ 0
Impairment of long-lived assets to be disposed of	$ 13,000
Disposal Group, Held-for-sale, Not Discontinued Operations | Central America & U.S. Campuses
Goodwill [Line Items]
Number of subsidiaries with impaired long-lived assets (subsidiary) | subsidiary	2