Incentive Plan (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2012
Summary of Stock Options
Outstanding, beginning of period, Number of Options Granted	787,450
Options granted, Number of Options Granted	0
Options forfeited, Number of Options Granted	0
Options exercised, Number of Options Granted	(105,700)
Options expired, Number of Options Granted	0
Exercisable, end of period, Number of Options Granted	681,750
Outstanding, end of period, Number of Options Granted	681,750
Vested or expected to vest, end of period, Number of Options Granted	681,750
Outstanding, beginning of period, Weighted Average Exercise Price	$ 14.55
Options granted, Weighted Average Exercise Price	$ 0.00
Options forfeited, Weighted Average Exercise Price	$ 0.00
Options exercised, Weighted Average Exercise Price	$ 6.30
Options expired, Weighted Average Exercise Price	$ 0.00
Outstanding, end of period, Weighted Average Exercise Price	$ 15.83
Exercisable, end of period, Weighted Average Exercise Price	$ 15.83
Vested or expected to vest, end of period, Weighted Average Exercise Price	$ 15.83
Outstanding, end of period, Weighted Average Remaining Contractual Term (Years)	3 years 26 days
Exercisable, end of period, Weighted Average Remaining Contractual Term (Years)	3 years 26 days
Vested or expected to vest, end of period, Weighted Average Remaining Contractual Term (Years)	3 years 26 days
Outstanding, end of period, Aggregate Intrinsic Value	$ 1,455
Exercisable, end of period, Aggregate Intrinsic Value	1,455
Vested or expected to vest, end of period, Aggregate Intrinsic Value	$ 1,455