Note 5 - Investments Schedule of Unrealized Losses (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015 security	Dec. 31, 2014 security
Continuous Loss Position Less Than Twelve Months
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year	49	62
Fair value available-for-sale securities	$ 102,674	$ 144,626
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	1,471	2,379
Continuous Unrealized Loss Position, Twelve Months Or Greater
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year	3	2
Fair value available-for-sale securities	9,442	4,482
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	276	154
Continuous Loss Position, Total
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	52	64
Fair value available-for-sale securities	112,116	149,108
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	1,747	2,533
US government and agency securities
Continuous Loss Position Less Than Twelve Months
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year		0
Fair value available-for-sale securities		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss		0
Continuous Unrealized Loss Position, Twelve Months Or Greater
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year		1
Fair value available-for-sale securities		3,455
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		6
Continuous Loss Position, Total
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions		1
Fair value available-for-sale securities		3,455
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		6
Corporate bonds and notes
Continuous Loss Position Less Than Twelve Months
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year	22	24
Fair value available-for-sale securities	41,307	40,917
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	445	410
Continuous Unrealized Loss Position, Twelve Months Or Greater
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year	1	1
Fair value available-for-sale securities	1,024	1,027
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	166	148
Continuous Loss Position, Total
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	23	25
Fair value available-for-sale securities	42,331	41,944
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	611	558
CMBS
Continuous Loss Position Less Than Twelve Months
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year	1
Fair value available-for-sale securities	2,057
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	2
Continuous Unrealized Loss Position, Twelve Months Or Greater
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year	0
Fair value available-for-sale securities	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Continuous Loss Position, Total
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	1
Fair value available-for-sale securities	2,057
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	2
Other ABS
Continuous Loss Position Less Than Twelve Months
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year	21	34
Fair value available-for-sale securities	54,604	97,356
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	817	1,727
Continuous Unrealized Loss Position, Twelve Months Or Greater
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year	2	0
Fair value available-for-sale securities	8,418	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	110	0
Continuous Loss Position, Total
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	23	34
Fair value available-for-sale securities	63,022	97,356
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	927	1,727
Foreign government securities
Continuous Loss Position Less Than Twelve Months
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year	5	4
Fair value available-for-sale securities	4,706	6,353
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	207	242
Continuous Unrealized Loss Position, Twelve Months Or Greater
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year	0	0
Fair value available-for-sale securities	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Continuous Loss Position, Total
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	5	4
Fair value available-for-sale securities	4,706	6,353
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 207	$ 242

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