Income/Loss Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Numerator
Loss from continuing operations	$ (14,550)	$ (4,744)	$ (11,945)	$ (33,630)	$ (23,704)	$ (13,169)	$ (23,642)	$ (17,997)	$ (64,869)	$ (78,512)	$ (2,350)
Income (loss) from discontinued operations	103	(1,076)	(1,151)	(1,510)	(1,547)	(1,088)	(1,278)	243	(3,634)	(3,670)	9,042
Net income (loss)	$ (14,447)	$ (5,820)	$ (13,096)	$ (35,140)	$ (25,251)	$ (14,257)	$ (24,920)	$ (17,754)	$ (68,503)	$ (82,182)	$ 6,692
Weighted-average common shares outstanding:
Basic (in shares)									45,102	44,897	43,285
Assumed conversion of employee stock options (in shares)									0	0	281
Assumed conversion of Platinum Warrant (in shares)									0	0	8,754
Weighted-average shares outstanding (diluted)									45,102	44,897	52,320
Net income (loss) per basic share:
Loss from continuing operations (in dollars per share)	$ (0.32)	$ (0.11)	$ (0.26)	$ (0.75)	$ (0.53)	$ (0.29)	$ (0.53)	$ (0.40)	$ (1.44)	$ (1.75)	$ (0.05)
Income (loss) from discontinued operations (in dollars per share)	$ 0.00	$ (0.02)	$ (0.03)	$ (0.03)	$ (0.03)	$ (0.03)	$ (0.03)	$ 0.00	$ (0.08)	$ (0.08)	$ 0.21
Net income (loss) (in dollars per share)	$ (0.32)	$ (0.13)	$ (0.29)	$ (0.78)	$ (0.56)	$ (0.32)	$ (0.56)	$ (0.40)	$ (1.52)	$ (1.83)	$ 0.16
Net income (loss) per diluted share:
Loss from continuing operations (in dollars per share)	$ (0.32)	$ (0.11)	$ (0.26)	$ (0.75)	$ (0.53)	$ (0.29)	$ (0.53)	$ (0.40)	$ (1.44)	$ (1.75)	$ (0.04)
Income (loss) from discontinued operations (in dollars per share)	$ 0.00	$ (0.02)	$ (0.03)	$ (0.03)	$ (0.03)	$ (0.03)	$ (0.03)	$ 0.00	$ (0.08)	$ (0.08)	$ 0.17
Net income (loss) (in dollars per share)	$ (0.32)	$ (0.13)	$ (0.29)	$ (0.78)	$ (0.56)	$ (0.32)	$ (0.56)	$ (0.40)	$ (1.52)	$ (1.83)	$ 0.13