Stock-Based Compensation (Tables)

3 Months Ended

Jun. 30, 2015

Share-based Compensation Arrangement by Share-based Payment Award

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

	Three Months Ended June 30,
	2015		2014
Stock options	$	2,805	$	3,264
Restricted stock and restricted stock units	13,898		11,206
Employee stock purchase plan	325		288
Affiliate management equity plans	1,301		1,301
Performance share units	536		192
Employee stock trust	6		129
Total stock-based compensation expense	$	18,871	$	16,380

Schedule of Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding [Table Text Block]

	Three Months Ended June 30,
	2015				2014
	Number of Shares		Weighted-Average Exercise Price Per Share		Number of Shares		Weighted-Average Exercise Price Per Share
Options outstanding at March 31	4,432		$	39.58	4,801		$	43.02
Granted	876		54.52		916		47.64
Exercised	(161	)	32.94		(236	)	30.84
Canceled/forfeited	(5	)	84.31		(37	)	70.04
Options outstanding at June 30	5,142		$	42.29	5,444		$	44.14

Management [Member]

Share-based Compensation Arrangement by Share-based Payment Award

Assumptions used to determine the weighted-average fair value of option grants

	Three Months Ended June 30,
	2015		2014
Expected dividend yield	1.18	%	1.04	%
Risk-free interest rate	1.44	%	1.51	%
Expected volatility	24.37	%	29.53	%
Expected life (in years)	4.97		4.94

Chief Executive Officer [Member]

Share-based Compensation Arrangement by Share-based Payment Award

Assumptions used to determine the weighted-average fair value of option grants

Expected dividend yield	1.48	%
Risk-free interest rate	0.86	%
Expected volatility	44.05	%

Key Employees

Share-based Compensation Arrangement by Share-based Payment Award

Assumptions used to determine the weighted-average fair value of option grants

	2015		2014
Expected dividend yield	1.46	%	1.33	%
Risk-free interest rate	0.86	%	0.75	%
Expected volatility	22.63	%	30.81	%