Consolidated Statements of Cumulative Redeemable Preferred Shares and Shareholders' Equity - USD ($) $ in Thousands	Total	Ordinary Shares	Treasury Shares	Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	Previously Reported	Previously Reported Ordinary Shares	Previously Reported Treasury Shares	Previously Reported Paid-In Capital	Previously Reported Accumulated Other Comprehensive Loss	Previously Reported Accumulated Deficit	Retroactive application of recapitalization	Retroactive application of recapitalization Ordinary Shares	Retroactive application of recapitalization Treasury Shares	Retroactive application of recapitalization Paid-In Capital
Beginning balance (in shares) at Dec. 31, 2015		50,481,822	0					60,249,330	5,373,884					(9,767,508)	(5,373,884)
Beginning balance at Dec. 31, 2015	$ 193,715	$ 5,386	$ 0	$ 393,034	$ (4,067)	$ (200,638)	$ 193,715	$ 656	$ (23,108)	$ 420,872	$ (4,067)	$ (200,638)	$ 0	$ 4,730	$ 23,108	$ (27,838)
Shareholders' Equity
Net income (loss)	20,216					20,216
Benefit obligation gain (loss), net of tax	348				348
Dividends on cumulative redeemable preferred shares	(43,676)			(43,676)
Ending balance (in shares) at Dec. 31, 2016		50,481,822	0
Ending balance at Dec. 31, 2016	$ 170,603	$ 5,386	$ 0	349,358	(3,719)	(180,422)
Beginning balance (in shares) at Dec. 31, 2015	32,738,094						32,738,094
Beginning balance at Dec. 31, 2015	$ 352,275						$ 352,275
Cumulative Redeemable Preferred Shares
Redemption of cumulative redeemable preferred shares (in shares)	(4,227,100)
Redemption of cumulative redeemable preferred shares	$ (35,508)
Payment of accrued dividends of cumulative redeemable preferred shares	(14,492)
Dividends on cumulative redeemable preferred shares	43,676
Purchase of cumulative redeemable preferred shares	0
Settlement of accrued dividends of cumulative redeemable preferred shares	$ 0
Ending balance (in shares) at Dec. 31, 2016	28,510,994
Ending balance at Dec. 31, 2016	$ 345,951
Shareholders' Equity
Net income (loss)	(241)					(241)
Benefit obligation gain (loss), net of tax	(107)				(107)
Share-based compensation (in shares)		151,569
Share-based compensation	3,765	$ 17		3,748
Recapitalization transaction (in shares)		52,982,364
Recapitalization transaction	433,531	$ 5,653		427,878
Dividends on cumulative redeemable preferred shares	(7,922)			(7,922)
Non-cash transfer of ordinary shares / Repurchase of ordinary shares (in shares)		(7,367)	(7,367)
Non-cash transfer of ordinary shares / Repurchase of ordinary shares	(80)		$ (80)
Issuance of ordinary shares in exchange for warrants (in shares)		6,689,309
Issuance of ordinary shares in exchange for warrants	0	$ 747		132		(879)
Ending balance (in shares) at Dec. 31, 2017		110,297,697	7,367
Ending balance at Dec. 31, 2017	599,549	$ 11,803	$ (80)	773,194	(3,826)	(181,542)
Cumulative Redeemable Preferred Shares
Dividends on cumulative redeemable preferred shares	$ 7,922
Purchase of cumulative redeemable preferred shares (in shares)	(28,510,994)
Purchase of cumulative redeemable preferred shares	$ (239,492)
Settlement of accrued dividends of cumulative redeemable preferred shares	$ (114,381)
Ending balance (in shares) at Dec. 31, 2017	0
Ending balance at Dec. 31, 2017	$ 0
Shareholders' Equity
Net income (loss)	18,977					18,977
Benefit obligation gain (loss), net of tax	168				168
Share-based compensation (in shares)		189,670
Share-based compensation	6,116	$ 22		6,094
Non-cash transfer of ordinary shares / Repurchase of ordinary shares (in shares)		(47,241)	(47,241)
Non-cash transfer of ordinary shares / Repurchase of ordinary shares	(314)		$ (314)
Shares issued in business combination (see Note 4) (in shares)		20,000,000
Shares issued in business combination (see Note 4)	215,400	$ 2,336		213,064
Repurchase of Earnout Warrants (see Note 10)	(55)			(55)
Ending balance (in shares) at Dec. 31, 2018		130,440,126	54,608
Ending balance at Dec. 31, 2018	839,841	$ 14,161	$ (394)	$ 992,297	$ (3,658)	$ (162,565)
Cumulative Redeemable Preferred Shares
Purchase of cumulative redeemable preferred shares	0
Settlement of accrued dividends of cumulative redeemable preferred shares	$ 0
Ending balance (in shares) at Dec. 31, 2018	0
Ending balance at Dec. 31, 2018	$ 0