Unaudited Selected Quarterly Financial Information (Schedule of Quarterly Financial Information) (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 12 Months Ended
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Unaudited Selected Quarterly Financial Information [Abstract]                      
Total revenue $ 90,071 $ 93,684 $ 97,197 $ 91,450 $ 88,004 $ 81,417 $ 80,836 $ 87,109 $ 372,402 $ 337,366 $ 389,428
Total expense 84,984 83,849 87,922 83,761 82,404 76,689 78,794 80,697 340,516 318,584 378,348
Income (loss) before tax 5,087 9,835 9,275 7,689 5,600 4,728 2,042 6,412 31,886 18,782 11,080
Income tax expense (benefit) 1,641 3,137 2,899 2,346 1,833 1,265 391 1,864 10,023 5,353 2,835
Net income (loss) $ 3,446 $ 6,698 $ 6,376 $ 5,343 $ 3,767 $ 3,463 $ 1,651 $ 4,548 21,863 13,429 8,245
Net income (loss) attributable to Hallmark Financial Services, Inc.                 $ 21,863 $ 13,429 $ 8,245
Basic earnings (loss) per share: $ 0.18 $ 0.35 $ 0.33 $ 0.28 $ 0.20 $ 0.18 $ 0.09 $ 0.24 $ 1.14 $ 0.70 $ 0.43
Diluted earnings (loss) per share: $ 0.17 $ 0.35 $ 0.33 $ 0.28 $ 0.19 $ 0.18 $ 0.09 $ 0.23 $ 1.13 $ 0.69 $ 0.43