Segment Information - Selected Financial Data by Business Segment (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenues	$ 85,984	$ 102,115	$ 265,464	$ 301,817
Income (loss) before income taxes	3,351	(327)	3,447	(39,306)	$ (45,100)
Total assets	419,047		419,047		400,074
Insurance
Segment Reporting Information [Line Items]
Revenues	85,966	102,099	265,413	300,533
Income (loss) before income taxes	4,850	1,173	7,792	(36,280)
Total assets	375,206		375,206		354,008
Real estate and Corporate
Segment Reporting Information [Line Items]
Revenues	18	16	51	1,284
Income (loss) before income taxes	(1,499)	$ (1,500)	(4,345)	$ (3,026)
Total assets	$ 43,841		$ 43,841		$ 46,066