Segment Information, Geographic operations (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 250,514	$ 257,866	$ 706,132	$ 704,625
Long-lived assets	1,108,133		1,108,133		1,106,338
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	150,252	159,622	437,567	442,498
Long-lived assets	878,627		878,627		888,032
Austria [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	211,742		211,742		201,224
Europe and Africa [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	64,995	59,315	166,486	155,216
Other international operations [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	35,267	38,929	102,079	106,911
Long-lived assets	$ 17,764		$ 17,764		$ 17,082