Stock-Based Compensation - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 2,766
Post-Tax	419	$ 196
Pre-Tax	530	248
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	156
Post-Tax	293	189
Pre-Tax	$ 371	$ 239

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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