Acquisitions (Details) $ in Thousands			3 Months Ended			6 Months Ended	12 Months Ended
	May 31, 2019 USD ($)	Jan. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($) item	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Aggregate purchase price of this acquisition was allocated on a preliminary basis
Issuance of seller notes at fair value						$ 5,345
Goodwill				$ 226,732	$ 198,742	226,732	$ 198,742	$ 196,343
Goodwill						27,961	2,399
2019 Acquisition Activity, prosthetic and orthotic business
Acquisitions
Acquisition-related costs				300		500
Aggregate purchase price of this acquisition was allocated on a preliminary basis
Cash paid, net of cash acquired	$ 200	$ 27,700		27,916		27,916
Issuance of seller notes at fair value	300	4,400				4,686
Additional consideration			$ 700			659
Aggregate purchase price	$ 500	$ 32,800				33,261
Accounts receivable, net				3,561		3,561
Inventories				1,558		1,558
Other assets				413		413
Accounts payable				(1,264)		(1,264)
Accrued expenses and other liabilities				(1,714)		(1,714)
Net assets acquired				5,271		5,271
Goodwill				27,990		27,990
2019 Acquisition Activity, prosthetic and orthotic business | Customer Relationships
Aggregate purchase price of this acquisition was allocated on a preliminary basis
Other intangible assets, net				2,368		$ 2,368
Useful life						3 years
2019 Acquisition Activity, prosthetic and orthotic business | Non-compete agreements
Aggregate purchase price of this acquisition was allocated on a preliminary basis
Other intangible assets, net				$ 349		$ 349
Useful life						4 years 10 months 24 days
2019 Acquisition Activity, prosthetic and orthotic business | Minimum
Acquisitions
Notes payable to share holders in quarterly installments period						3 years
2019 Acquisition Activity, prosthetic and orthotic business | Maximum
Acquisitions
Notes payable to share holders in quarterly installments period						5 years
2018 Acquisition Activity, two O&P businesses
Acquisitions
Number of businesses acquired | item					2
Aggregate purchase price of this acquisition was allocated on a preliminary basis
Cash paid, net of cash acquired					$ 1,978		1,978
Issuance of seller notes at fair value							1,120
Aggregate purchase price					3,100		3,098
Accounts receivable, net					256		256
Inventories					302		302
Other assets					90		90
Accounts payable					(59)		(59)
Accrued expenses and other liabilities					(364)		(364)
Net assets acquired					699		699
Goodwill					2,399		2,399
2018 Acquisition Activity, two O&P businesses | Customer Relationships
Aggregate purchase price of this acquisition was allocated on a preliminary basis
Other intangible assets, net					260		$ 260
Useful life							4 years
2018 Acquisition Activity, two O&P businesses | Non-compete agreements
Aggregate purchase price of this acquisition was allocated on a preliminary basis
Other intangible assets, net					$ 214		$ 214
Useful life							4 years 7 months 6 days