Investments Aging of Unrealized Losses by Class (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013 security		Mar. 31, 2012 security
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	$ 11		$ 18
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	436		331
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	76,653		46,794
Available-for-sale, Securities in Unrealized Loss Positions, Twelve Months or More, Qualitative Disclosure, Number of Positions	5	[1]	4	[1]
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	577		413
Available-for-sale, Securities in Unrealized Loss Positions, Less Than Twelve Months, Qualitative Disclosure, Number of Positions	53	[1]	30	[1]
U.S. government and agency securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	0		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	259		289
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	37,774		44,174
Available-for-sale, Securities in Unrealized Loss Positions, Twelve Months or More, Qualitative Disclosure, Number of Positions	0	[1]	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0		0
Available-for-sale, Securities in Unrealized Loss Positions, Less Than Twelve Months, Qualitative Disclosure, Number of Positions	16		13
States, municipalities and political subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	22
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	4,892
Available-for-sale, Securities in Unrealized Loss Positions, Twelve Months or More, Qualitative Disclosure, Number of Positions	0	[1]
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Available-for-sale, Securities in Unrealized Loss Positions, Less Than Twelve Months, Qualitative Disclosure, Number of Positions	5
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	0		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	147		1
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	33,842		2,000
Available-for-sale, Securities in Unrealized Loss Positions, Twelve Months or More, Qualitative Disclosure, Number of Positions	0	[1]	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0		0
Available-for-sale, Securities in Unrealized Loss Positions, Less Than Twelve Months, Qualitative Disclosure, Number of Positions	29		1
Redeemable Preferred Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	0		1
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	0		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0		0
Available-for-sale, Securities in Unrealized Loss Positions, Twelve Months or More, Qualitative Disclosure, Number of Positions	1	[1]	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	102		102
Available-for-sale, Securities in Unrealized Loss Positions, Less Than Twelve Months, Qualitative Disclosure, Number of Positions	0		0
Fixed Maturities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	0		1
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	428		290
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	76,508		46,174
Available-for-sale, Securities in Unrealized Loss Positions, Twelve Months or More, Qualitative Disclosure, Number of Positions	1	[1]	1	[1]
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	102		102
Available-for-sale, Securities in Unrealized Loss Positions, Less Than Twelve Months, Qualitative Disclosure, Number of Positions	50	[1]	14	[1]
Common Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	3		3
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	8		41
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	145		620
Available-for-sale, Securities in Unrealized Loss Positions, Twelve Months or More, Qualitative Disclosure, Number of Positions	2		1
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	211		53
Available-for-sale, Securities in Unrealized Loss Positions, Less Than Twelve Months, Qualitative Disclosure, Number of Positions	3		16
Nonredeemable Preferred Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	8		14
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	0		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0		0
Available-for-sale, Securities in Unrealized Loss Positions, Twelve Months or More, Qualitative Disclosure, Number of Positions	2		2
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	264		258
Available-for-sale, Securities in Unrealized Loss Positions, Less Than Twelve Months, Qualitative Disclosure, Number of Positions	0		0
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	11		17
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses	8		41
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	145		620
Available-for-sale, Securities in Unrealized Loss Positions, Twelve Months or More, Qualitative Disclosure, Number of Positions	4	[1]	3	[1]
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 475		$ 311
Available-for-sale, Securities in Unrealized Loss Positions, Less Than Twelve Months, Qualitative Disclosure, Number of Positions	3	[1]	16	[1]

[1] This amount represents the actual number of discrete securities, not the number of shares of those securities. The numbers are not presented in thousands.