Schedule I - Condensed Financial Information of the Registrant (Parent Company Only) Cash Flows Statement (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating activities:
Cash used in operating activities	$ (6,352)	$ (48,923)	$ (148,092)
Investing activities:
Proceeds from the sale of debt and equity securities	1,068	7,938	31,036
Purchases of debt and equity securities	(1,511)	(2,316)	(11,046)
Purchases of property, plant and equipment	(318)	(3,108)	(5,270)
Net cash provided by (used in) investing activities	7,617	106,593	(4,892)
Financing activities:
Payment of withholding taxes on exercise of restricted stock units	(46)	(496)	(5,737)
Cash provided by (used in) financing activities	2,315	(63,248)	76,027
Net increase (decrease) in cash and cash equivalents	3,580	(5,578)	(75,061)
Cash and cash equivalents, beginning of year	56,462	62,677
Cash and cash equivalents, end of year	60,542	56,462	62,677
Supplemental disclosure of cash flow information:
Payment (refund) of federal and state income taxes	124	(67)	(3,817)
Non-cash investing and financing activities:
Issuance of common stock for vested restricted stock units	348	1,609	11,463
Parent Company
Operating activities:
Cash used in operating activities	(13,372)	(5,997)	(3,439)
Investing activities:
Proceeds from the sale of debt and equity securities	135	10,153	6,027
Purchases of debt and equity securities			(264)
Purchases of and advances to subsidiaries		(18,563)	(8,376)
Cash received from the repayment of loans and advances to subsidiaries		12,496	8,909
Dividends and other distributions received from subsidiaries	9,565		12,088
Purchases of property, plant and equipment		(8)	(39)
Net cash provided by (used in) investing activities	9,700	4,078	18,345
Financing activities:
Loans from subsidiaries	3,500
Payment of withholding taxes on exercise of restricted stock units		(126)	(4,118)
Cash provided by (used in) financing activities	3,500	(126)	(4,118)
Net increase (decrease) in cash and cash equivalents	(172)	(2,045)	10,788
Cash and cash equivalents, beginning of year	11,429	13,474	2,686
Cash and cash equivalents, end of year	11,257	11,429	13,474
Supplemental disclosure of cash flow information:
Payment (refund) of federal and state income taxes	226	3	4,127
Non-cash investing and financing activities:
Issuance of common stock for vested restricted stock units	85	559	7,464
Dividend received from subsidiaries			$ 62,600