Restructuring (Details) (USD $)	3 Months Ended			6 Months Ended	12 Months Ended
	Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2012	Dec. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Restructuring [Abstract]
Restructuring accrual of severance and related benefits		$ 1,500,000	$ 1,900,000	$ 1,300,000
Lease termination payments	1,359,000
Activity in restructuring accrual [Roll Forward]
Balance at beginning of period		813,000			813,000	731,000	0
Additions, net					2,866,000	2,092,000	1,641,000
Payments					(3,679,000)	(2,010,000)	(910,000)
Balance at end of period				731,000	0	813,000	731,000
Severance and Related Benefits [Member]
Activity in restructuring accrual [Roll Forward]
Balance at beginning of period		813,000			813,000	571,000	0
Additions, net					1,492,000	1,905,000	1,341,000
Payments					(2,305,000)	(1,663,000)	(770,000)
Balance at end of period				571,000	0	813,000	571,000
Other Exit Costs [Member]
Activity in restructuring accrual [Roll Forward]
Balance at beginning of period		0			0	6,000	0
Additions, net					15,000	184,000	8,000
Payments					(15,000)	(190,000)	(2,000)
Balance at end of period				6,000	0	0	6,000
Contract Termination Costs [Member]
Activity in restructuring accrual [Roll Forward]
Balance at beginning of period		0			0	154,000	0
Additions, net					1,359,000	3,000	292,000
Payments					(1,359,000)	(157,000)	(138,000)
Balance at end of period				$ 154,000	$ 0	$ 0	$ 154,000