Leases (Maturities of lease liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 31, 2020
Finance Lease Liabilities Payments Due [Abstract]
2020	$ 194,978
2021	154,457
2022	122,986
2023	92,915
2024	65,825
Thereafter	35,155
Total lease payments	666,316
Less: imputed interest	0
Financing lease liability	666,316
Operating Lease Liabilities Payments Due [Abstract]
2020	24,802
2021	22,598
2022	21,780
2023	20,791
2024	6,213
Thereafter	65,758
Total lease payments	161,942
Less: inputed interest	(55,328)
Operating lease liability	$ 106,614	$ 106,443