Leases - Summary of minimum future rental payments required (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Operating Leases
2019	$ 8,357
2020	17,133
2021	16,988
2022	16,851
2023	11,039
Thereafter	140,698
Total undiscounted rental payments	211,066
Less imputed interest	(106,271)
Lease liabilities	104,795
Operating Leases
2019		$ 16,627
2020		17,183
2021		17,124
2022		17,450
2023		11,390
Thereafter		140,562
Total undiscounted rental payments		220,336
Finance Leases
2020	1,699
2021	2,106
2022	10,440
2023	2,418
2024	0
Thereafter	0
Total undiscounted rental payments	16,663
Less imputed interest	(1,673)
Total lease liabilities	$ 14,990
Finance Leases
2019		2,106
2020		2,106
2021		10,440
2022		2,418
2023		0
Thereafter		0
Total undiscounted rental payments		$ 17,070

Amount of minimum lease payments for capital leases.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in remainder of fiscal year following latest fiscal year ended.

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