Commitments (Lease Commitments for Leases having Terms of More than One Year) (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2020	$ 20,852
2021	18,495
2022	16,750
2023	16,317
2024	15,736
Thereafter	54,683
Total	142,833
Property Plant and Equipment, Ground [Member]
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2020	1,024
2021	1,024
2022	1,030
2023	1,030
2024	1,031
Thereafter	48,619
Total	53,758
Property, Plant and Equipment, Operating [Member]
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2020	18,536
2021	17,471
2022	15,720
2023	15,287
2024	14,705
Thereafter	6,064
Total	87,783
Rental Equipment [Member]
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2020	1,292
2021
2022
2023
2024
Thereafter
Total	$ 1,292

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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