Goodwill and intangible assets - Additional information (Details) $ in Thousands	3 Months Ended
	Sep. 30, 2018 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible amortization expense	$ 53,489
Estimated amortization expense, year ending June 30, 2019	196,984
Estimated amortization expense, year ending June 30, 2020	186,587
Estimated amortization expense, year ending June 30, 2021	181,969
Estimated amortization expense, year ending June 30, 2022	176,074
Estimated amortization expense, year ending June 30, 2023	$ 168,554