CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Hill Share of Stockholders' Equity	Common Stock	Additional Paid-in Capital	Accumulated (Deficit)	Accumulated Other Comprehensive (Loss)	Treasury Stock	Non-controlling Interests
Common stock, balance at beginning of period (in shares) at Dec. 31, 2020			62,920
Treasury stock, balance at beginning of period (in shares) at Dec. 31, 2020							6,807
Balance at beginning of period at Dec. 31, 2020	$ 109,288	$ 107,736	$ 6	$ 215,010	$ (79,542)	$ 1,318	$ (29,056)	$ 1,552
Increase (decrease) in stockholders' equity
Net earnings (loss)	(2,977)	(3,184)			(3,184)			207
Other comprehensive income (loss)	(1,556)	(297)				(297)		(1,259)
Share-based compensation expense (in shares)			270
Share-based compensation expense	1,371	1,371		1,371
Share issued under employee stock purchase plan (in shares)			44
Shares issued under employee stock purchase plan	95	95		95
Common stock, balance at end of period (in shares) at Jun. 30, 2021			63,234
Treasury stock, balance at end of period (in shares) at Jun. 30, 2021							6,807
Balance at end of period at Jun. 30, 2021	106,221	105,721	$ 6	216,476	(82,726)	1,021	$ (29,056)	500
Common stock, balance at beginning of period (in shares) at Dec. 31, 2020			62,920
Treasury stock, balance at beginning of period (in shares) at Dec. 31, 2020							6,807
Balance at beginning of period at Dec. 31, 2020	109,288	107,736	$ 6	215,010	(79,542)	1,318	$ (29,056)	1,552
Increase (decrease) in stockholders' equity
Net earnings (loss)	(1,659)
Common stock, balance at end of period (in shares) at Sep. 30, 2021			63,249
Treasury stock, balance at end of period (in shares) at Sep. 30, 2021							6,807
Balance at end of period at Sep. 30, 2021	106,827	106,359	$ 6	216,942	(81,467)	(66)	$ (29,056)	468
Common stock, balance at beginning of period (in shares) at Jun. 30, 2021			63,234
Treasury stock, balance at beginning of period (in shares) at Jun. 30, 2021							6,807
Balance at beginning of period at Jun. 30, 2021	106,221	105,721	$ 6	216,476	(82,726)	1,021	$ (29,056)	500
Increase (decrease) in stockholders' equity
Net earnings (loss)	1,317	1,259			1,259			58
Other comprehensive income (loss)	(1,177)	(1,087)				(1,087)		(90)
Share-based compensation expense (in shares)			3
Share-based compensation expense	443	443		443
Share issued under employee stock purchase plan (in shares)			12
Shares issued under employee stock purchase plan	23	23		23
Common stock, balance at end of period (in shares) at Sep. 30, 2021			63,249
Treasury stock, balance at end of period (in shares) at Sep. 30, 2021							6,807
Balance at end of period at Sep. 30, 2021	$ 106,827	106,359	$ 6	216,942	(81,467)	(66)	$ (29,056)	468
Common stock, balance at beginning of period (in shares) at Dec. 31, 2021	63,291		63,291
Treasury stock, balance at beginning of period (in shares) at Dec. 31, 2021	6,807						6,807
Balance at beginning of period at Dec. 31, 2021	$ 103,239	102,795	$ 6	217,471	(83,813)	(1,813)	$ (29,056)	444
Increase (decrease) in stockholders' equity
Net earnings (loss)	789	886			886			(97)
Other comprehensive income (loss)	(4,510)	(4,650)				(4,650)		140
Share-based compensation expense (in shares)			331
Share-based compensation expense	771	771		771
Share issued under employee stock purchase plan (in shares)			42
Shares issued under employee stock purchase plan	56	56		56
Common stock, balance at end of period (in shares) at Jun. 30, 2022			63,664
Treasury stock, balance at end of period (in shares) at Jun. 30, 2022							6,807
Balance at end of period at Jun. 30, 2022	$ 100,345	99,858	$ 6	218,298	(82,927)	(6,463)	$ (29,056)	487
Common stock, balance at beginning of period (in shares) at Dec. 31, 2021	63,291		63,291
Treasury stock, balance at beginning of period (in shares) at Dec. 31, 2021	6,807						6,807
Balance at beginning of period at Dec. 31, 2021	$ 103,239	102,795	$ 6	217,471	(83,813)	(1,813)	$ (29,056)	444
Increase (decrease) in stockholders' equity
Net earnings (loss)	$ 86
Common stock, balance at end of period (in shares) at Sep. 30, 2022	63,664		63,674
Treasury stock, balance at end of period (in shares) at Sep. 30, 2022	6,807						6,807
Balance at end of period at Sep. 30, 2022	$ 97,557	97,108	$ 6	219,116	(83,616)	(9,342)	$ (29,056)	449
Common stock, balance at beginning of period (in shares) at Jun. 30, 2022			63,664
Treasury stock, balance at beginning of period (in shares) at Jun. 30, 2022							6,807
Balance at beginning of period at Jun. 30, 2022	100,345	99,858	$ 6	218,298	(82,927)	(6,463)	$ (29,056)	487
Increase (decrease) in stockholders' equity
Net earnings (loss)	(703)	(689)			(689)			(14)
Other comprehensive income (loss)	(2,903)	(2,879)				(2,879)		(24)
Share-based compensation expense (in shares)			10
Share-based compensation expense	818	818		818
Shares issued under employee stock purchase plan	$ 0
Common stock, balance at end of period (in shares) at Sep. 30, 2022	63,664		63,674
Treasury stock, balance at end of period (in shares) at Sep. 30, 2022	6,807						6,807
Balance at end of period at Sep. 30, 2022	$ 97,557	$ 97,108	$ 6	$ 219,116	$ (83,616)	$ (9,342)	$ (29,056)	$ 449