Common Shares Level 4 (Details) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Weighted Average Common Shares Outstanding Basic and Diluted [Line Items]
Weighted Average Number of Shares Outstanding, Basic	58,264	58,744	58,088	59,000
Weighted Average Number Diluted Shares Outstanding Adjustment	528	636	464	741
Weighted Average Number of Shares Outstanding, Diluted	58,792	59,380	58,552	59,741