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Income Taxes (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items] |  |  |  |  |
Effective Income Tax Rate, Percent | 26.10% | 21.10% | 24.10% | 13.00% |
Valuation Allowance [Abstract] |  |  |  |  |
Valuation Allowance, Amount | $ 0 |  | $ 0 |  | $ 0
Income Tax Uncertainties [Abstract] |  |  |  |  |
Unrecognized Tax Benefits that Would Impact Effective Tax Rate | 3,900 |  | 3,900 |  | 3,600
Unrecognized Tax Benefits, Period Increase (Decrease) | 400 | $ (700) | 300 | $ (1,900) |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued | 900 |  | 900 |  | $ 1,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense | (300) | $ (600) | (400) | $ (1,400) |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |  |  |
Balance beginning of period |  |  | 4,585 |  |
Additions based on tax positions related to current year |  |  | 1,180 |  |
Additions for tax positions of prior years |  |  | 124 |  |
Reductions for tax positions of prior years |  |  | (60) |  |
Reductions due to lapse of applicable statute of limitations |  |  | (867) |  |
Settlements |  |  | (76) |  |
Balance end of period | 4,886 |  | 4,886 |  |
Maximum [Member] |  |  |  |  |
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items] |  |  |  |  |
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound | 1,000 |  | 1,000 |  |
Minimum [Member] |  |  |  |  |
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items] |  |  |  |  |
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound | $ 0 |  | $ 0 |  |

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- Definition The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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