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

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- Definition

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

+ References

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- Definition

The amount of plan compensation cost recognized during the period.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Stock Based Compensation Summary (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	$ 18,171	$ 18,193	$ 37,041	$ 34,699
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	2,234	2,953	5,039	6,217
Management Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Deferred Compensation Arrangement with Individual, Compensation Expense	1,302	1,301	2,603	2,603
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	12,455	12,083	26,353	23,289
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Employee Stock Ownership Plan (ESOP), Compensation Expense	116	109	440	398
Rabbi trust [Domain]
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	7	32	13	160
Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	1,150	1,425	1,150	1,550
Key Employees
Share-based Compensation Arrangement by Share-based Payment Award
Deferred Compensation Arrangement with Individual, Compensation Expense	$ 907	$ 290	$ 1,443	$ 482