Consolidated Statement of Equity (Statement) (USD $)	Total	Parent [Member]	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Noncontrolling Interest [Member]
Stockholders' Equity Beginning, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2010				$ 235,000	$ 209,198,000	$ 432,843,000	$ (111,000)	$ 76,000
Shares issued pursuant to sale of equity				0
Exercise of stock options				2,814
Issuance of stock awards, net of forfeitures				242,334
Retirement of treasury shares				(72,516)			(72,516)
Purchase of treasury shares							87,588
Issuance of treasury shares							(15,072)
Non-employee directors' deferred compensation plan							0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued pursuant to sale of equity				0	0
Purchase of treasury shares							(3,143,000)
Issuance of stock awards, net of forfeitures				1,000
Exercise of stock options					0
Share-based Compensation expense	8,781,000				8,781,000
Issuance of treasury shares					(472,000)		472,000
Retirement of treasury shares					(2,671,000)		2,671,000
Tax benefit (detriment) of stock-based compensation					785,000
Contribution by investing partner in PDCM	12,464,000				12,464,000
Effect of PDCM deconsolidation/change in ownership interest					(10,378,000)
Non-employee directors' deferred compensation plan							0
Net income (Loss) attributable to shareholders						13,437,000
Net loss attributed to noncontrolling interest in subsidiary								(76,000)
Stockholders' Equity Ending, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2011	664,112,000	664,112,000	0	236,000	217,707,000	446,280,000	(111,000)	0
Shares, Issued at Dec. 31, 2011				23,634,958			2,938
Shares end of year at Dec. 31, 2011				23,632,020
Shares issued pursuant to sale of equity				6,500,000
Exercise of stock options				0
Issuance of stock awards, net of forfeitures				173,737
Retirement of treasury shares				(14,471)			(14,471)
Purchase of treasury shares							44,576
Issuance of treasury shares							(28,587)
Non-employee directors' deferred compensation plan							603
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued pursuant to sale of equity				65,000	164,431,000
Purchase of treasury shares							(1,500,000)
Issuance of stock awards, net of forfeitures				2,000
Exercise of stock options					0
Share-based Compensation expense	8,495,000				8,495,000
Issuance of treasury shares					(955,000)		955,000
Retirement of treasury shares					(491,000)		491,000
Tax benefit (detriment) of stock-based compensation					(1,693,000)
Contribution by investing partner in PDCM	0				0
Effect of PDCM deconsolidation/change in ownership interest					0
Non-employee directors' deferred compensation plan							(19,000)
Net income (Loss) attributable to shareholders						(130,712,000)
Net loss attributed to noncontrolling interest in subsidiary								0
Stockholders' Equity Ending, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2012	703,181,000	703,181,000	0	303,000	387,494,000	315,568,000	(184,000)	0
Shares, Issued at Dec. 31, 2012				30,294,224			5,059
Shares end of year at Dec. 31, 2012				30,289,165
Shares issued pursuant to sale of equity				5,175,000
Exercise of stock options				10,763
Issuance of stock awards, net of forfeitures				212,926
Retirement of treasury shares				(17,257)			(17,257)
Purchase of treasury shares							84,642
Issuance of treasury shares							(67,334)
Non-employee directors' deferred compensation plan							398
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued pursuant to sale of equity				52,000	275,795,000
Purchase of treasury shares							(4,133,000)
Issuance of stock awards, net of forfeitures				2,000
Exercise of stock options					125,000
Share-based Compensation expense	12,880,000				12,402,000
Issuance of treasury shares					(3,270,000)		3,271,000
Retirement of treasury shares					(824,000)		824,000
Tax benefit (detriment) of stock-based compensation					2,489,000
Contribution by investing partner in PDCM	0				0
Effect of PDCM deconsolidation/change in ownership interest					0
Non-employee directors' deferred compensation plan							(19,000)
Net income (Loss) attributable to shareholders						(22,301,000)
Net loss attributed to noncontrolling interest in subsidiary								0
Stockholders' Equity Ending, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2013	$ 967,594,000	$ 967,594,000	$ 0	$ 357,000	$ 674,211,000	$ 293,267,000	$ (241,000)	$ 0
Shares, Issued at Dec. 31, 2013				35,675,656			5,508
Shares end of year at Dec. 31, 2013				35,670,148