Compensation and Employee Benefit Plans [Text Block] (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Proceeds from Stock Options Exercised	$ 44	$ 60
Payments Related to Tax Withholding for Share-based Compensation	$ 2,384	$ 0
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 8.31
Proceeds from Stock Options Exercised	$ 44
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	4,968
Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options	731
Payments Related to Tax Withholding for Share-based Compensation	$ 2,384

Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

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- Definition

Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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-Topic 718
-SubTopic 10
-Section 25
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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
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-Publisher FASB
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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