Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2016	Mar. 31, 2015
Allowance for doubtful accounts receivable	$ 26,959	$ 27,016
Preferred stock, shares authorized	20,030,000	20,030,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	87,795,000	87,554,000
Treasury stock, shares	15,151,000	12,197,000