Business Segments (Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Reconciliations of total assets from reportable segments to the condensed consolidated balance sheets
Total assets for reportable segments	$ 1,408,151	$ 1,169,933
Unallocated cash and cash equivalents	263,009	225,143	$ 369,442	$ 245,088
Consolidated total assets	1,408,151	1,169,933
Reportable segments
Reconciliations of total assets from reportable segments to the condensed consolidated balance sheets
Total assets for reportable segments	896,253	698,174
Consolidated total assets	896,253	698,174
Unallocated to segments
Reconciliations of total assets from reportable segments to the condensed consolidated balance sheets
Unallocated cash and cash equivalents	263,009	225,143
Unallocated deferred tax assets	23,661	29,083
Other unallocated corporate assets	$ 225,228	$ 217,533