Fair Value Measurements (Financial Assets And Liabilities Measured At Fair Value On Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Assets:
Money market funds	$ 1,625	$ 137,145	$ 241,991
Trading securities associated with deferred compensation plans	17,386	17,726	17,210
Interest rate swap agreements	4,516	2,149	853
Forward foreign currency exchange contracts	379	973	4
Total financial assets measured and reported at fair value	23,906	157,993	260,058
Liabilities:
Guarantees of bank loans to tobacco growers	1,149	1,177	1,844
Forward foreign currency exchange contracts	15	175	1,229
Total financial liabilities measured and reported at fair value	1,164	1,352	3,073
Net Asset Value (NAV) [Member]
Assets:
Money market funds	1,625	137,145	241,991
Trading securities associated with deferred compensation plans	0	0	0
Interest rate swap agreements	0	0	0
Forward foreign currency exchange contracts	0	0	0
Total financial assets measured and reported at fair value	1,625	137,145	241,991
Liabilities:
Guarantees of bank loans to tobacco growers	0	0	0
Forward foreign currency exchange contracts	0	0	0
Total financial liabilities measured and reported at fair value	0	0	0
Level 1 [Member]
Assets:
Money market funds	0	0	0
Trading securities associated with deferred compensation plans	17,386	17,726	17,210
Interest rate swap agreements	0	0	0
Forward foreign currency exchange contracts	0	0	0
Total financial assets measured and reported at fair value	17,386	17,726	17,210
Liabilities:
Guarantees of bank loans to tobacco growers	0	0	0
Forward foreign currency exchange contracts	0	0	0
Total financial liabilities measured and reported at fair value	0	0	0
Level 2 [Member]
Assets:
Money market funds	0	0	0
Trading securities associated with deferred compensation plans	0	0	0
Interest rate swap agreements	4,516	2,149	853
Forward foreign currency exchange contracts	379	973	4
Total financial assets measured and reported at fair value	4,895	3,122	857
Liabilities:
Guarantees of bank loans to tobacco growers	0	0	0
Forward foreign currency exchange contracts	15	175	1,229
Total financial liabilities measured and reported at fair value	15	175	1,229
Level 3 [Member]
Assets:
Money market funds	0	0	0
Trading securities associated with deferred compensation plans	0	0	0
Interest rate swap agreements	0	0	0
Forward foreign currency exchange contracts	0	0	0
Total financial assets measured and reported at fair value	0	0	0
Liabilities:
Guarantees of bank loans to tobacco growers	1,149	1,177	1,844
Forward foreign currency exchange contracts	0	0	0
Total financial liabilities measured and reported at fair value	$ 1,149	$ 1,177	$ 1,844