Convertible Subordinated Notes Convertible Subordinated Notes (Narrative) (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) $ / shares	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) $ / shares	Sep. 30, 2019 USD ($)	Sep. 09, 2020 USD ($)	Dec. 31, 2019 USD ($) $ / shares	Mar. 19, 2014
Debt Instrument [Line Items]
Common Stock, Par or Stated Value Per Share | $ / shares	$ 0.01		$ 0.01			$ 0.01
Adjustments to Additional Paid in Capital, Other	$ 828,000		$ 828,000
Debt Instrument, Convertible, Conversion Ratio			45.8380
Credit Facility amortization of debt issuance costs			$ 592,000	$ 289,000
Debt instrument, convertible, conversion price (in dollars per share) | $ / shares	$ 21.82		$ 21.82
Interest Expense	$ 8,007,000	$ 6,283,000	$ 24,787,000	18,907,000
Repurchase of the 2.75% convertible subordinated notes			4,563,000	27,000
Payments for Repurchase of Redeemable Convertible Preferred Stock, Cash Payment			4,500,000
Convertible Preferred Stock, Nonredeemable or Redeemable, Issuer Option, Value					$ 3,800,000
Convertible Preferred Stock, Percentage Redeemed					60.00%
Additional Paid-in Capital
Debt Instrument [Line Items]
Adjustments to Additional Paid in Capital, Other	$ 828,000		$ 828,000
Convertible Subordinated Notes [Member]
Debt Instrument [Line Items]
Convertible subordinated notes, principal amount						$ 6,319,000
Stated interest rate percentage	2.75%		2.75%				2.75%
Long-term Debt, Fair Value	$ 2,900,000		$ 2,900,000
Acquisition debt imputed interest expense	43,000	43,000	130,000	131,000
Credit Facility amortization of debt issuance costs	9,000	$ 6,000	$ 21,000	19,000
Debt Instrument, Convertible, Remaining Discount Amortization Period			5 months
Debt Instrument, Discount Rate		11.40%
Accretion of discount, convertible subordinated notes	69,000	$ 61,000	$ 200,000	$ 178,000
Carrying value of the liability component	$ 2,522,000		$ 2,522,000		$ 2,559,000	$ 5,971,000
Debt Instrument, Unamortized Debt Issuance Costs	3.20%	3.20%	3.10%	3.20%
Accrued Liabilities	$ 100,000		$ 100,000