Leases - Future minimum payments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Operating lease liabilities under Topic 842
Operating leases - Remaining 2021	$ 7,611
Operating leases - 2022	28,880
Operating leases - 2023	26,677
Operating leases - 2024	25,396
Operating leases - 2025	22,458
Operating leases - later years	61,399
Operating leases - Total	172,421
Less: Imputed interest	(20,382)
Operating lease liabilities	152,039	$ 152,588
Finance lease liabilities under Topic 842
Finance leases - Remaining 2021	839
Finance leases - 2022	3,402
Finance leases - 2023	3,492
Finance leases - 2024	3,589
Finance leases - 2025	3,701
Finance leases - later years	8,851
Finance leases - Total	23,874
Less: imputed interest	(3,564)
Finance lease liabilities	$ 20,310	$ 22,572

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

No definition available.