Income Taxes - US Tax Reform (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2017
Income Taxes
Provision at statutory income tax rate (as a percent)		21.00%	35.00%
Provisional tax amount	$ 12.4

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
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