Stock Based Compensation and Stock Options (Details 3) (USD $)	3 Months Ended
Jun. 30, 2013
Stock options outstanding and exercisable
Number of Outstanding Options	1,199,630
Weighted Average Remaining Contractual Life	3 years 7 months 17 days
Outstanding Options-Weighted Average Exercise Price	$ 19.60
Exercisable Options-Number of Exercisable Options	516,511
Exercisable Options-Weighted Average Exercise Price	$ 15.14
Range of Exercise Price, $7.78 to $15.00 [Member]
Stock options outstanding and exercisable
Range of Exercise Price, lower limit	$ 7.78
Range of Exercise Price, upper limit	$ 15.00
Number of Outstanding Options	329,834
Weighted Average Remaining Contractual Life	2 years 6 months
Outstanding Options-Weighted Average Exercise Price	$ 11.72
Exercisable Options-Number of Exercisable Options	310,691
Exercisable Options-Weighted Average Exercise Price	$ 11.74
Range of Exercise Price, $15.01 to $22.07 [Member]
Stock options outstanding and exercisable
Range of Exercise Price, lower limit	$ 15.01
Range of Exercise Price, upper limit	$ 22.07
Number of Outstanding Options	310,713
Weighted Average Remaining Contractual Life	4 years 1 month 17 days
Outstanding Options-Weighted Average Exercise Price	$ 19.87
Exercisable Options-Number of Exercisable Options	142,877
Exercisable Options-Weighted Average Exercise Price	$ 18.67
Range of Exercise Price, $22.08 to $23.35 [Member]
Stock options outstanding and exercisable
Range of Exercise Price, lower limit	$ 22.08
Range of Exercise Price, upper limit	$ 23.35
Number of Outstanding Options	300,534
Weighted Average Remaining Contractual Life	4 years 15 days
Outstanding Options-Weighted Average Exercise Price	$ 23.09
Exercisable Options-Number of Exercisable Options	39,270
Exercisable Options-Weighted Average Exercise Price	$ 23.11
Range of Exercise Price, $23.36 to $29.27 [Member]
Stock options outstanding and exercisable
Range of Exercise Price, lower limit	$ 23.36
Range of Exercise Price, upper limit	$ 29.27
Number of Outstanding Options	258,549
Weighted Average Remaining Contractual Life	4 years
Outstanding Options-Weighted Average Exercise Price	$ 25.26
Exercisable Options-Number of Exercisable Options	23,673
Exercisable Options-Weighted Average Exercise Price	$ 25.26

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ 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 (c)(1)(iii)

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

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ 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 (g)

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

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ 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 (c)(iii)

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

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ 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 (c)(1)(i)-(ii)

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

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ 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 (c)(1)(i)-(ii)

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

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- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (e)(1)

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

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ 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 (g)

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

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