Supplemental Condensed Consolidating Financial Information Condensed consolidating cash flows (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011	Dec. 31, 2010
Condensed Financial Statements, Captions [Line Items]
Net loss	$ (17,336)	$ (12,522)
Loss on change in fair value of debt	8,951	4,331
Net cash used in operating activities	(11,259)	(16,807)
Payments to Acquire Interest in Subsidiaries and Affiliates	99	0
Net cash provided by investing activities	21,850	3,835
Redemption of senior unsecured debentures	(583)	0
Net cash (used in) provided by financing activities	(583)	132
Cash and Cash Equivalents, Period Increase (Decrease)	10,008	(12,840)
Cash and Cash Equivalents, at Carrying Value	90,821		80,813	90,821	80,813	72,646	85,486
Common stock issued	0	132
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net loss	(17,336)	(11,251)
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Change Due to Net Income Attributable to Parent and Effects of Changes, Net	(16,397)	(10,899)
Loss on change in fair value of debt	0	0
Other Operating Activities, Cash Flow Statement	853	(6,205)
Net cash used in operating activities	(86)	(6,557)
Proceeds from Sale, Maturity and Collection of Investments	0	0
Payments to Acquire Investments	0	0
Payments to Acquire Interest in Subsidiaries and Affiliates	0
Payments for (Proceeds from) Other Investing Activities	0	0
Net cash provided by investing activities	0	0
Redemption of senior unsecured debentures	0
Net cash (used in) provided by financing activities	0	132
Cash and Cash Equivalents, Period Increase (Decrease)	(86)	(6,425)
Cash and Cash Equivalents, at Carrying Value	1,846	15,964	1,932		22,389
Common stock issued		132
Subsidiary Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Net loss	(17,069)	(12,595)
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Change Due to Net Income Attributable to Parent and Effects of Changes, Net	(3,770)	(3,926)
Loss on change in fair value of debt	7,702	2,075
Other Operating Activities, Cash Flow Statement	2,360	490
Net cash used in operating activities	(3,237)	(6,104)
Proceeds from Sale, Maturity and Collection of Investments	13,638	0
Payments to Acquire Investments	(1,012)	0
Payments to Acquire Interest in Subsidiaries and Affiliates	0
Payments for (Proceeds from) Other Investing Activities	(2,225)	(3)
Net cash provided by investing activities	10,401	(3)
Redemption of senior unsecured debentures	(583)
Net cash (used in) provided by financing activities	(583)	6,631
Cash and Cash Equivalents, Period Increase (Decrease)	6,581	524
Cash and Cash Equivalents, at Carrying Value	12,952	1,397	6,371		873
Common stock issued		6,631
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net loss	(3,098)	(3,501)
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Change Due to Net Income Attributable to Parent and Effects of Changes, Net	0	0
Loss on change in fair value of debt	1,249	2,256
Other Operating Activities, Cash Flow Statement	(6,087)	(9,532)
Net cash used in operating activities	(7,936)	(10,777)
Proceeds from Sale, Maturity and Collection of Investments	9,622	37,356
Payments to Acquire Investments	(215)	(33,173)
Payments to Acquire Interest in Subsidiaries and Affiliates	0
Payments for (Proceeds from) Other Investing Activities	2,042	(345)
Net cash provided by investing activities	11,449	3,838
Redemption of senior unsecured debentures	0
Net cash (used in) provided by financing activities	0	0
Cash and Cash Equivalents, Period Increase (Decrease)	3,513	(6,939)
Cash and Cash Equivalents, at Carrying Value	76,023	55,285	72,510		62,224
Common stock issued		0
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net loss	20,167	14,825
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Change Due to Net Income Attributable to Parent and Effects of Changes, Net	20,167	14,825
Loss on change in fair value of debt	0	0
Other Operating Activities, Cash Flow Statement	0	6,631
Net cash used in operating activities	0	6,631
Proceeds from Sale, Maturity and Collection of Investments	0	0
Payments to Acquire Investments	0	0
Payments to Acquire Interest in Subsidiaries and Affiliates	0
Payments for (Proceeds from) Other Investing Activities	0	0
Net cash provided by investing activities	0	0
Redemption of senior unsecured debentures	0
Net cash (used in) provided by financing activities	0	(6,631)
Cash and Cash Equivalents, Period Increase (Decrease)	0	0
Cash and Cash Equivalents, at Carrying Value	0	0	0		0
Common stock issued		(6,631)
Consolidated Entities [Member]
Condensed Financial Statements, Captions [Line Items]
Net loss	(17,336)	(12,522)
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Change Due to Net Income Attributable to Parent and Effects of Changes, Net	0	0
Loss on change in fair value of debt	8,951	4,331
Other Operating Activities, Cash Flow Statement	(2,874)	(8,616)
Net cash used in operating activities	(11,259)	(16,807)
Proceeds from Sale, Maturity and Collection of Investments	23,260	37,356
Payments to Acquire Investments	(1,227)	(33,173)
Payments to Acquire Interest in Subsidiaries and Affiliates	0
Payments for (Proceeds from) Other Investing Activities	(183)	(348)
Net cash provided by investing activities	21,850	3,835
Redemption of senior unsecured debentures	(583)
Net cash (used in) provided by financing activities	(583)	132
Cash and Cash Equivalents, Period Increase (Decrease)	10,008	(12,840)
Cash and Cash Equivalents, at Carrying Value	90,821	72,646	80,813		85,486
Common stock issued		$ 132