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
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 30
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- Definition

The amount of plan compensation cost recognized during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 40
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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, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	$ 18,463	$ 17,510	$ 39,531	$ 54,981
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	1,921	2,042	4,146	4,284
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	13,509	12,741	30,088	27,314
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Employee Stock Ownership Plan (ESOP), Compensation Expense	96	116	393	417
Rabbi trust [Domain]
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	8	7	14	13
Director [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense	1,075	1,150	1,075	1,150
Key Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Deferred Compensation Arrangement with Individual, Compensation Expense	1,078	1,019	2,263	1,869
Subsidiaries [Member] \| Management Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Deferred Compensation Arrangement with Individual, Compensation Expense	$ 776	$ 435	$ 1,552	$ 19,934