Acquisitions Martin Currie (Pension Details) (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Mar. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax	$ 119
Martin Currie [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets	5.40%	5.40%
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	$ 25	$ 28
Defined Benefit Plan, Fair Value of Plan Assets	62,893		$ 59,623
Defined Benefit Plan, Benefit Obligation	99,802		97,137
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(36,909)		(37,514)
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax	(17,202)		$ (16,681)
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 1,919
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	2.70%	2.70%
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year	$ 0
Fair Value, Inputs, Level 2 [Member] \| Bonds [Member] \| Martin Currie [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	34.00%		35.00%
Defined Benefit Plan, Target Allocation Percentage	0.4
Fair Value, Inputs, Level 1 [Member] \| Cash [Member] \| Martin Currie [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	1.00%
Fair Value, Inputs, Level 1 [Member] \| Equity [Member] \| Martin Currie [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	65.00%		65.00%
Defined Benefit Plan, Target Allocation Percentage	0.6

Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

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Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Amount of contributions expected to be received by defined benefit plan from employer in fiscal year. Excludes contributions paid by employer in current fiscal year.

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Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of net periodic benefit cost (credit) for defined benefit plan.

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Description of target allocation percentages, or range of percentages, considering the major categories of plan assets as of the latest statement of financial position presented (on a weighted-average basis for employers with more than one plan) that are pertinent to an understanding of the plan investment policies and strategies.

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Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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