Stock-Based Compensation Stock Based Compensation Summary (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	$ 18,871	$ 16,380
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	2,805	3,264
Management Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Deferred Compensation Arrangement with Individual, Compensation Expense	1,301	1,301
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	13,898	11,206
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Employee Stock Ownership Plan (ESOP), Compensation Expense	325	288
Rabbi trust [Domain]
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	6	129
Key Employees
Share-based Compensation Arrangement by Share-based Payment Award
Deferred Compensation Arrangement with Individual, Compensation Expense	$ 536	$ 192

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

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The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

+ References

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

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-Name Accounting Standards Codification

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The amount of plan compensation cost recognized during the period.

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+ References

No definition available.

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