SCHEDULE II-CONDENSED FINANCIAL INFORMATION OF REGISTRANT (PARENT COMPANY) (Details) - 10K (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
ASSETS
Cash	$ 30,620	$ 39,469	$ 44,314	$ 81,184
Short-term investments, at cost which approximates fair value	16,339	23,232
Investments in unconsolidated investee, at equity value	60,046	49,793
Fixed income:
Available-for-sale, at fair value (amortized cost - $46,226 in 2014 and $18,839 in 2013)	1,495,087	1,440,052
Property and equipment, at cost, net of accumulated depreciation of $528 in 2014 and $312 in 2013	42,549	40,261
Total assets	2,775,542	2,740,310
Liabilities:
Bonds payable, long-term debt	149,625	149,582
Total Liabilities	1,930,480	1,911,344
Shareholders' Equity
Common stock ($1 par value, authorized 100,000,000 shares, issued 66,032,929 shares in 2014 and 65,912,638 shares in 2013, and outstanding 43,102,715 shares in 2014 and 42,982,424 shares in 2013)	66,033	65,913
Paid-in capital	213,737	208,705
Accumulated other comprehensive earnings, net of tax	171,383	136,027
Retained earnings	786,908	811,320
Deferred compensation	13,769	11,562
Treasury shares at cost (22,930,214 shares in 2014 and 2013)	(406,768)	(404,561)
Total shareholders' equity	845,062	828,966	796,363	792,634
Total liabilities and shareholders' equity	2,775,542	2,740,310
PARENT COMPANY
ASSETS
Cash	374	181	14,023	346
Short-term investments, at cost which approximates fair value	177	13,394
Accounts receivable, affiliates	3,803	2,350
Investments in subsidiaries, at equity value	903,738	905,620
Investments in unconsolidated investee, at equity value	54,316	49,793
Fixed income:
Available-for-sale, at fair value (amortized cost - $46,226 in 2014 and $18,839 in 2013)	46,136	18,447
Property and equipment, at cost, net of accumulated depreciation of $528 in 2014 and $312 in 2013	3,208	3,446
Income taxes receivable - current	463	493
Deferred debt costs	1,258	1,398
Other assets	681	190
Total assets	1,014,154	995,312
Liabilities:
Income taxes payable--deferred	16,372	14,485
Bonds payable, long-term debt	149,625	149,582
Interest payable, long-term debt	2,153	1,808
Other liabilities	942	471
Total Liabilities	169,092	166,346
Shareholders' Equity
Common stock ($1 par value, authorized 100,000,000 shares, issued 66,032,929 shares in 2014 and 65,912,638 shares in 2013, and outstanding 43,102,715 shares in 2014 and 42,982,424 shares in 2013)	66,033	65,913
Paid-in capital	213,737	208,705
Accumulated other comprehensive earnings, net of tax	171,383	136,027
Retained earnings	786,908	811,320
Deferred compensation	13,769	11,562
Treasury shares at cost (22,930,214 shares in 2014 and 2013)	(406,768)	(404,561)
Total shareholders' equity	845,062	828,966
Total liabilities and shareholders' equity	$ 1,014,154	$ 995,312