CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands		Total	Hill Share of Stockholders' Equity	Common Stock	Additional Paid-in Capital	Retained Earnings (Deficit)	Accumulated Other Comprehensive (Loss)	Treasury Stock	Non-controlling Interests
Balance at beginning of period (in shares) at Dec. 31, 2018				62,181				6,546
Balance at beginning of period at Dec. 31, 2018		$ 94,445	$ 93,840	$ 6	$ 210,084	$ (85,444)	$ (2,575)	$ (28,231)	$ 605
Increase (decrease) in stockholders' equity
Net earnings (loss)		(2,068)	(2,135)			(2,135)			67
Other comprehensive income (loss)		(1,854)	(1,806)				(1,806)		(48)
Stock issued to Board of Directors (in shares)				24
Stock issued to Board of Directors		0
Stock-based compensation expense	[1]	241	241		241
Balance at end of period (in shares) at Mar. 31, 2019				62,205				6,546
Balance at end of period at Mar. 31, 2019		90,764	90,140	$ 6	210,325	(87,579)	(4,381)	$ (28,231)	624
Balance at beginning of period (in shares) at Dec. 31, 2018				62,181				6,546
Balance at beginning of period at Dec. 31, 2018		94,445	93,840	$ 6	210,084	(85,444)	(2,575)	$ (28,231)	605
Increase (decrease) in stockholders' equity
Net earnings (loss)		(368)
Balance at end of period (in shares) at Jun. 30, 2019				62,262				6,546
Balance at end of period at Jun. 30, 2019		94,358	93,539	$ 6	211,239	(85,962)	(3,513)	$ (28,231)	819
Balance at beginning of period (in shares) at Mar. 31, 2019				62,205				6,546
Balance at beginning of period at Mar. 31, 2019		90,764	90,140	$ 6	210,325	(87,579)	(4,381)	$ (28,231)	624
Increase (decrease) in stockholders' equity
Net earnings (loss)		1,700	1,617			1,617			83
Other comprehensive income (loss)		980	868				868		112
Stock-based compensation expense		801	801		801
Stock issued under employee stock purchase plan (in shares)				57
Stock issued under employee stock purchase plan		113	113		113
Balance at end of period (in shares) at Jun. 30, 2019				62,262				6,546
Balance at end of period at Jun. 30, 2019		$ 94,358	93,539	$ 6	211,239	(85,962)	(3,513)	$ (28,231)	819
Balance at beginning of period (in shares) at Dec. 31, 2019		62,708		62,708				6,546
Balance at beginning of period at Dec. 31, 2019		$ 110,228	109,357	$ 6	212,759	(71,360)	(3,817)	$ (28,231)	871
Increase (decrease) in stockholders' equity
Net earnings (loss)		(6,422)	(6,581)			(6,581)			159
Other comprehensive income (loss)		(255)	(96)				(96)		(159)
Stock-based compensation expense		399	399		399
Stock issued under employee stock purchase plan (in shares)	[2]			83
Stock issued under employee stock purchase plan	[2]	105	105		105
Transfer of shares pledged as collateral (in shares)	[1]			261				261
Transfer of shares pledged as collateral	[1]	(825)	(825)					$ (825)
Balance at end of period (in shares) at Mar. 31, 2020				62,530				6,807
Balance at end of period at Mar. 31, 2020		$ 103,230	102,359	$ 6	213,263	(77,941)	(3,913)	$ (29,056)	871
Balance at beginning of period (in shares) at Dec. 31, 2019		62,708		62,708				6,546
Balance at beginning of period at Dec. 31, 2019		$ 110,228	109,357	$ 6	212,759	(71,360)	(3,817)	$ (28,231)	871
Increase (decrease) in stockholders' equity
Net earnings (loss)		$ (8,358)
Balance at end of period (in shares) at Jun. 30, 2020		62,609		62,609				6,807
Balance at end of period at Jun. 30, 2020		$ 107,193	106,495	$ 6	214,161	(79,895)	1,279	$ (29,056)	698
Balance at beginning of period (in shares) at Mar. 31, 2020				62,530				6,807
Balance at beginning of period at Mar. 31, 2020		103,230	102,359	$ 6	213,263	(77,941)	(3,913)	$ (29,056)	871
Increase (decrease) in stockholders' equity
Net earnings (loss)		(1,936)	(1,954)			(1,954)			18
Other comprehensive income (loss)		5,001	5,192				5,192		(191)
Stock-based compensation expense		802	802		802
Stock issued under employee stock purchase plan (in shares)				79
Stock issued under employee stock purchase plan		$ 96	96		96
Balance at end of period (in shares) at Jun. 30, 2020		62,609		62,609				6,807
Balance at end of period at Jun. 30, 2020		$ 107,193	$ 106,495	$ 6	$ 214,161	$ (79,895)	$ 1,279	$ (29,056)	$ 698

[1] Reflects 261 shares of the Company's common stock pledged as collateral under the terms of a secured promissory note payable to the Company. During the three months ended March 31, 2020, the Company exercised its right to retain the shares upon the note holder's agreement to relinquish the shares upon the promissory note maturity date.

[2] Includes $55 of proceeds related to shares issued under the Employee Stock Purchase Plan ("ESPP") during the three months ended March 31, 2020 and received during the three months ended June 30, 2020. The six months ended June 30, 2019 excluded $34 of proceeds received during the period that are included in Hill International, Inc.'s (the "Company") consolidated statements of cash flow, but related to ESPP shares issued and recognized at December 31, 2018.