Revision of Previously Reported Financial Information Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Goodwill	$ 24,122	$ 23,409	$ 0
Total assets	4,092,086	4,026,428
Other non-current liabilities	76,682	113,242
Total liabilities	2,688,682	2,808,892
Accumulated deficit	(303,557)	(467,747)
Total Amkor stockholders’ equity	1,383,588	1,200,286
Total equity	1,403,404	1,217,536	$ 1,129,449	$ 963,808
Total liabilities and equity	$ 4,092,086	4,026,428
Scenario, Previously Reported [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Goodwill		19,443
Total assets		4,022,462
Other non-current liabilities		101,679
Total liabilities		2,797,329
Accumulated deficit		(460,150)
Total Amkor stockholders’ equity		1,207,883
Total equity		1,225,133
Total liabilities and equity		4,022,462
Scenario, Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Goodwill		3,966
Total assets		3,966
Other non-current liabilities		11,563
Total liabilities		11,563
Accumulated deficit		(7,597)
Total Amkor stockholders’ equity		(7,597)
Total equity		(7,597)
Total liabilities and equity		$ 3,966