Acquisition of SafeOp Surgical, Inc. - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended		3 Months Ended			9 Months Ended		12 Months Ended
	Mar. 09, 2018	Mar. 08, 2018	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Business Acquisition [Line Items]
Recognition of beneficial conversion feature SafeOp convertible notes			$ 200
Accretion to contingent consideration								$ 289	$ 646
SafeOp Surgical, Inc.
Business Acquisition [Line Items]
Business acquisition date	Mar. 09, 2018
Cash paid	$ 15,100									$ 15,100
Stock issued for acquisition, value		$ 9,800				$ 697	$ 364
Closing share price		$ 3.30
Convertible notes issued				$ 3,000
Convertible note convertible to common stock				987,578
Number of warrants issued				2,200,000
Exercise price of warrants per share				$ 3.50
Warrant issued to purchase of common stock and purchase of common stock period				5 years
Convertible note, maturity date				Mar. 09, 2019
Accretion to contingent consideration								300
SafeOp Surgical, Inc. | Interest Expense
Business Acquisition [Line Items]
Recognition of beneficial conversion feature SafeOp convertible notes								$ 200
SafeOp Surgical, Inc. | Common Stock
Business Acquisition [Line Items]
Number of shares of common stock issued	3,265,132
Stock issued for acquisition		2,975,209			886,843	174,302	115,621	886,843		443,421