Fair Value Measurements (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases, (Sales), Issuances, (Settlements) [Abstract]
Cash and cash equivalents	$ 3,752,000	$ 1,765,000	$ 2,158,000	$ 2,584,000
Aggregate Principal of convertible notes	150,000,000
Cash Convertible Notes Hedge [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases, (Sales), Issuances, (Settlements) [Abstract]
Balance at beginning of period	48,025,000
Purchases into Level 3	0
Issuances into Level 3	0
Gains/(Losses) included in Earnings	(424,000)
Balance at end of period	47,601,000
Fifth Amended Credit Facility [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases, (Sales), Issuances, (Settlements) [Abstract]
Carrying Amount of Outstanding borrowings under the Fifth Amended Credit Agreement	112,900,000
Fair Value of Outstanding borrowings under the Fifth Amended Credit Agreement	112,300,000
Cash Convertible Notes [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases, (Sales), Issuances, (Settlements) [Abstract]
Aggregate Principal of convertible notes	150,000,000
Debt Instrument, Carrying Amount	124,900,000
Debt Instrument, Fair Value	175,100,000
Cash Conversion Derivative [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases, (Sales), Issuances, (Settlements) [Abstract]
Balance at beginning of period	(48,025,000)
Purchases into Level 3	0
Issuances into Level 3	0
Gains/(Losses) included in Earnings	424,000
Balance at end of period	(47,601,000)
CareFirst Convertible Note [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases, (Sales), Issuances, (Settlements) [Abstract]
Debt Instrument, Carrying Amount	20,000,000
Debt Instrument, Fair Value	20,000,000
Recurring [Member] | Foreign Exchange Contract [Member]
Assets measured at fair value on a recurring basis
Gross Fair Value	365,000	477,000
Netting	(205,000)	(111,000)
Net Fair Value	160,000	366,000
Liabilities measured at fair value on a recurring basis
Gross Fair Value	376,000	111,000
Netting	(205,000)	(111,000)
Net Fair Value	171,000	0
Recurring [Member] | Foreign Exchange Contract [Member] | Level 2 [Member]
Assets measured at fair value on a recurring basis
Gross Fair Value	365,000	477,000
Liabilities measured at fair value on a recurring basis
Gross Fair Value	376,000	111,000
Recurring [Member] | Foreign Exchange Contract [Member] | Level 3 [Member]
Assets measured at fair value on a recurring basis
Gross Fair Value	0	0
Liabilities measured at fair value on a recurring basis
Gross Fair Value	0	0
Recurring [Member] | Interest Rate Swap [Member]
Liabilities measured at fair value on a recurring basis
Gross Fair Value	524,000	395,000
Netting	0	0
Net Fair Value	524,000	395,000
Recurring [Member] | Interest Rate Swap [Member] | Level 2 [Member]
Liabilities measured at fair value on a recurring basis
Gross Fair Value	524,000	395,000
Recurring [Member] | Interest Rate Swap [Member] | Level 3 [Member]
Liabilities measured at fair value on a recurring basis
Gross Fair Value	0	0
Recurring [Member] | Cash Convertible Notes Hedge [Member]
Assets measured at fair value on a recurring basis
Gross Fair Value	47,601,000	48,025,000
Netting	0	0
Net Fair Value	47,601,000	48,025,000
Recurring [Member] | Cash Convertible Notes Hedge [Member] | Level 2 [Member]
Assets measured at fair value on a recurring basis
Gross Fair Value	0	0
Recurring [Member] | Cash Convertible Notes Hedge [Member] | Level 3 [Member]
Assets measured at fair value on a recurring basis
Gross Fair Value	47,601,000	48,025,000
Recurring [Member] | Cash Conversion Derivative [Member]
Liabilities measured at fair value on a recurring basis
Gross Fair Value	47,601,000	48,025,000
Netting	0	0
Net Fair Value	47,601,000	48,025,000
Recurring [Member] | Cash Conversion Derivative [Member] | Level 2 [Member]
Liabilities measured at fair value on a recurring basis
Gross Fair Value	0	0
Recurring [Member] | Cash Conversion Derivative [Member] | Level 3 [Member]
Liabilities measured at fair value on a recurring basis
Gross Fair Value	$ 47,601,000	$ 48,025,000