Basis of Presentation (Stock Option Narrative) (Details) (USD $)	3 Months Ended	9 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Stock-based compensation expense			$ 6,489,000us-gaap_ShareBasedCompensation	$ 5,245,000us-gaap_ShareBasedCompensation
Stock-Based Awards
Unamortized stock-based compensation expense related to unvested stock awards	24,700,000		24,700,000
Weighted average period of recognition for unrecognized compensation costs (in years)			2 years 339 days
Tax benefit attributable to stock options exercised			0	0
Stock-based compensation expense	2,400,000	2,100,000	5,800,000	4,800,000
Employee Stock Purchase Plan
Unamortized stock-based compensation expense related to unvested stock awards	200,000		200,000
Weighted average period of recognition for unrecognized compensation costs (in years)			0 years 6 months
Tax benefit attributable to stock options exercised			0	0
Percentage of market value price of common stock under Employee Stock Purchase Plan	85.00%		85.00%
Maximum contribution percentage amount of employee's base compensation	10.00%		10.00%
Stock-based compensation expense	$ 200,000	$ 100,000	$ 700,000	$ 400,000

No authoritative reference available.

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No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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