Business Segments (Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Mar. 31, 2016	Sep. 30, 2015	Mar. 31, 2015
Reconciliations of total assets from reportable segments to the condensed consolidated balance sheets
Total assets for reportable segments	$ 1,572,601	$ 1,278,068
Unallocated cash and cash equivalents	110,047	245,956	$ 99,775	$ 225,143
Consolidated total assets	1,572,601	1,278,068
Reportable segments
Reconciliations of total assets from reportable segments to the condensed consolidated balance sheets
Total assets for reportable segments	1,172,137	762,783
Consolidated total assets	1,172,137	762,783
Unallocated to segments
Reconciliations of total assets from reportable segments to the condensed consolidated balance sheets
Unallocated cash and cash equivalents	110,047	245,956
Unallocated deferred tax assets	21,574	20,636
Other unallocated corporate assets	$ 268,843	$ 248,693