SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

6 Months Ended

Jun. 30, 2013

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Schedule of reconciliation of numerator and denominator of the basic and diluted earnings per share computations

	For the Three-Month Period					For the Three-Month Period
	Ended June 30, 2013					Ended June 30, 2012
(in thousands, except	Income		Shares	Per Share		Income		Shares	Per Share
per share data)	(Numerator)		(Denominator)	Amount		(Numerator)		(Denominator)	Amount
Basic EPS
Income available to common shareholders	$	29,902	21,314	$	1.40	$	24,748	21,213	$	1.17
Effect of Dilutive Securities
Stock options	—		356			—		301
Diluted EPS
Income available to common shareholders	$	29,902	21,670	$	1.38	$	24,748	21,514	$	1.15

	For the Six-Month Period					For the Six-Month Period
	Ended June 30, 2013					Ended June 30, 2012
(in thousands, except	Income		Shares	Per Share		Income		Shares	Per Share
per share data)	(Numerator)		(Denominator)	Amount		(Numerator)		(Denominator)	Amount
Basic EPS
Income available to common shareholders	$	54,749	21,293	$	2.57	$	52,786	21,200	$	2.49
Effect of Dilutive Securities
Stock options	—		341			—		321
Diluted EPS
Income available to common shareholders	$	54,749	21,634	$	2.53	$	52,786	21,521	$	2.45

Schedule of changes in the balance of each component of accumulated other comprehensive earnings

	For the Three-Month Periods Ended June 30,				For the Six-Month Periods  Ended June 30,
(in thousands)	2013			2012	2013			2012
Unrealized Gains/Losses on Available-for-Sale Securities
Beginning balance	$	160,723		128,101	$	143,170		117,325
Other comprehensive earnings before reclassifications	(30,824		)	5,430	(10,557		)	24,939
Amounts reclassified from accumulated other comprehensive earnings	(2,657		)	460	(5,371		)	(8,273	)
Net current-period other comprehensive earnings	$	(33,481	)	5,890	$	(15,928	)	16,666
Ending balance	$	127,242		133,991	$	127,242		133,991

Schedule of effects of reclassifications out of accumulated other comprehensive earnings

	Amount Reclassified from Accumulated Other Comprehensive Earnings
(in thousands) Component of Accumulated	For the Three-Month Periods Ended June 30,					For the Six-Month Periods Ended June 30,					Affected line item in the
Other Comprehensive Earnings	2013			2012		2013			2012		Statement of Earnings
Unrealized gains and losses on available-for-sale securities	$4,087			447		$8,263			13,883		Net realized investment gains
	—			(1,156	)	—			(1,156	)	Other-than-temporary impairment (OTTI) losses on investments
	4,087			(709	)	8,263			12,727		Earnings before income taxes
	(1,430		)	249		(2,892		)	(4,454	)	Income tax expense
	$	2,657		(460	)	$	5,371		8,273		Net earnings