Financial Information of Registrant (Parent Company) (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
ASSETS
Deferred tax asset	$ 20,549	$ 35,641
Other assets	6,438	6,078
TOTAL ASSETS	395,859	400,074
Liabilities:
Debentures payable	40,348	40,302
Term loan from principal stockholder	29,805	29,779
Other liabilities	13,224	10,476
Stockholders' equity	64,757	72,488	$ 103,670	$ 106,964
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	395,859	400,074
Parent Company
ASSETS
Investment in subsidiaries, at equity in net assets	119,517	112,479
Cash and cash equivalents	2,310	3,457	$ 8,095	$ 15,836
Loan to wholly-owned subsidiary	19,610	23,610
Deferred tax asset	14,883	25,828
Other assets	1,671	1,655
TOTAL ASSETS	157,991	167,029
Liabilities:
Debentures payable	40,348	40,302
Term loan from principal stockholder	29,805	29,779
Other liabilities	23,081	24,460
Stockholders' equity	64,757	72,488
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 157,991	$ 167,029