Segment and Geographic Reporting (Reconciliation of Operating Profit (Loss) and Assets) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Interest income																	$ 46	$ 61	$ 71
Interest Expense																	4,108	58	63
Depreciation, Depletion and Amortization																	16,813	10,610	9,883
Income tax (benefit) expense																	(322)	780	734
Segment operating (loss) income																	(36,950)	394	2,947
Segment net (loss) income	(15,997)	[1],[2]	(13,944)	[1],[3]	(5,299)	[1],[4]	(5,661)	[1]	883	[5]	434	[6]	(728)	[6]	(959)	[6]	(40,901)	(370)	2,226
Capital expenditures																	6,722	4,620	3,079
Total assets	466,950								217,157								466,950	217,157		110,769
U.S. Medical
Segment Reporting Information [Line Items]
Interest income																	44	61	70
Interest Expense																	4,098	58	63
Depreciation, Depletion and Amortization																	15,205	9,217	8,705
Income tax (benefit) expense																	(887)	402	414
Segment operating (loss) income																	(39,267)	(1,276)	1,037
Segment net (loss) income																	(42,628)	(1,666)	656
Capital expenditures																	6,532	4,406	3,063
Total assets	432,151								198,639								432,151	198,639		95,181
International Medical
Segment Reporting Information [Line Items]
Interest income																	2	0	1
Interest Expense																	10	0	0
Depreciation, Depletion and Amortization																	1,608	1,393	1,178
Income tax (benefit) expense																	565	378	320
Segment operating (loss) income																	2,317	1,670	1,910
Segment net (loss) income																	1,727	1,296	1,570
Capital expenditures																	190	214	16
Total assets	$ 34,799								$ 18,518								$ 34,799	$ 18,518		$ 15,588

[1] During the first, second, third and fourth quarters of 2014, the Company incurred $0.3 million, $4.0 million, $3.8 million and $7.8 million, respectively, in transaction and integration costs related to the acquisition of AngioScore. See Note 2, “Business Combinations.”

[2] During the fourth quarter of 2014, the Company incurred $1.5 million in transaction costs related to the acquisition of the Stellarex DCB Assets. See Note 17, “Subsequent Event.”

[3] During the third quarter of 2014, the Company recorded an impairment charge of $4.1 million and a reduction of $1.1 million to the contingent consideration liability related to certain assets and liabilities recorded from the acquisition of Upstream in 2013. See Note 6, “Goodwill and Other Intangible Assets.”

[4] Net loss and net loss per share have been adjusted from the previously filed Form 10-Q as of June 30, 2014 to reflect adjustments made during the measurement period to provisional amounts recognized for the AngioScore acquisition at the acquisition date. The Company recorded a deferred tax benefit of $1.3 million related to a partial release of valuation allowance related to the AngioScore acquisition. See Note 14, “Income Taxes.”

[5] During the fourth quarter of 2013, the Company incurred $0.6 million of medical device excise tax expense, $0.2 million in contingent consideration expense, and $0.2 million in acquisition-related intangible asset amortization. In addition, during the fourth quarter of 2013, the Company recorded an intangible asset impairment of $4.5 million and an adjustment to the contingent consideration liability of $5.2 million related to certain assets and liabilities recorded from the acquisition of Upstream in 2013. See Note 6, “Goodwill and Other Intangible Assets.

[6] During each of the first, second and third quarters of 2013, the Company incurred $0.5 million of medical device excise tax (which commenced January 1, 2013), $0.2 million in contingent consideration expense, and $0.2 million in acquisition-related intangible asset amortization, respectively.