ACQUISITION (Details) (USD $)	3 Months Ended							12 Months Ended		3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2012 Casualty	Mar. 31, 2011 Casualty	Mar. 31, 2012 Surety	Mar. 31, 2011 Surety	Mar. 31, 2012 Contractors Bonding and Insurance Company Y person office	Mar. 31, 2012 Contractors Bonding and Insurance Company person office	Apr. 28, 2011 Contractors Bonding and Insurance Company	Mar. 31, 2012 Contractors Bonding and Insurance Company Casualty	Mar. 31, 2012 Contractors Bonding and Insurance Company Surety
Business acquisition
Business acquisition consideration paid in cash									$ 135,900,000
Number of contractors served by the acquiree							30,000	30,000
Number of regional branch offices operated by the acquiree							13	13
Number of insurance agents and brokers served by the acquiree							4,000	4,000
Amount of goodwill resulting from acquisition							20,400,000	20,400,000
Amount of separately identifiable intangible assets resulting from acquisition							14,500,000	14,500,000
Amount of separately identifiable intangible assets resulting from acquisition, net of related amortization							13,600,000	13,600,000
Business acquisition purchase accounting adjustments, maximum tenure (in years)							1
Premiums written							13,800,000	49,800,000		8,900,000	4,900,000
Pretax earnings contributed							500,000
Underwriting loss	(14,941,000)	(20,947,000)	(552,000)	(5,537,000)	(2,472,000)	(5,377,000)	500,000
Net investment income							1,000,000
Valuation of insurance policies in force, including value of business acquired							1,300,000	1,300,000	10,800,000
Unearned premium (UEP) acquired							$ 2,700,000	$ 2,700,000	$ 29,500,000
Percentage of unearned premium (UEP) acquired earned as revenue							91.00%	91.00%