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Stock Based Compensation Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range (Details) | 12 Months Ended
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Dec. 31, 2018 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Number of Stock Options Outstanding (in shares) | shares | 284,522
Weighted-Average Remaining Contractual Life (in years) | 5 years 5 months 9 days
Weighted-Average Exercise Price (in usd per share) | $ 25.67
Number of Stock Options Outstanding (in shares) | shares | 172,410
Weighted-Average Remaining Contractual Life (in years) | 3 years 8 months 5 days
Weighted-Average Exercise Price (in usd per share) | $ 22.55
Exercise Price Range $17.48 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Number of Stock Options Outstanding (in shares) | shares | 5,763
Weighted-Average Remaining Contractual Life (in years) | 22 days
Weighted-Average Exercise Price (in usd per share) | $ 17.48
Number of Stock Options Outstanding (in shares) | shares | 5,763
Weighted-Average Remaining Contractual Life (in years) | 22 days
Weighted-Average Exercise Price (in usd per share) | $ 17.48
Exercise Price Range $19.58 to $20.93 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Number of Stock Options Outstanding (in shares) | shares | 61,569
Weighted-Average Remaining Contractual Life (in years) | 1 year 7 months 24 days
Weighted-Average Exercise Price (in usd per share) | $ 20.32
Number of Stock Options Outstanding (in shares) | shares | 61,569
Weighted-Average Remaining Contractual Life (in years) | 1 year 7 months 24 days
Weighted-Average Exercise Price (in usd per share) | $ 20.32
Exercise Price Range $21.50 to $21.99 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Number of Stock Options Outstanding (in shares) | shares | 52,683
Weighted-Average Remaining Contractual Life (in years) | 3 years 9 months
Weighted-Average Exercise Price (in usd per share) | $ 21.81
Number of Stock Options Outstanding (in shares) | shares | 52,683
Weighted-Average Remaining Contractual Life (in years) | 3 years 9 months
Weighted-Average Exercise Price (in usd per share) | $ 21.81
Exercise Price Range $23.19 to $23.66 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Number of Stock Options Outstanding (in shares) | shares | 69,175
Weighted-Average Remaining Contractual Life (in years) | 6 years 4 months 2 days
Weighted-Average Exercise Price (in usd per share) | $ 23.45
Number of Stock Options Outstanding (in shares) | shares | 38,243
Weighted-Average Remaining Contractual Life (in years) | 6 years
Weighted-Average Exercise Price (in usd per share) | $ 23.40
Exercise Price Range $31.84 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Number of Stock Options Outstanding (in shares) | shares | 50,376
Weighted-Average Remaining Contractual Life (in years) | 9 years 1 month 2 days
Weighted-Average Exercise Price (in usd per share) | $ 31.84
Number of Stock Options Outstanding (in shares) | shares | 1,030
Weighted-Average Remaining Contractual Life (in years) | 9 years 1 month 2 days
Weighted-Average Exercise Price (in usd per share) | $ 31.84
Exercise Price Range $35.07 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Number of Stock Options Outstanding (in shares) | shares | 44,956
Weighted-Average Remaining Contractual Life (in years) | 7 years 10 months 10 days
Weighted-Average Exercise Price (in usd per share) | $ 35.07
Number of Stock Options Outstanding (in shares) | shares | 13,122
Weighted-Average Remaining Contractual Life (in years) | 7 years 4 months 10 days
Weighted-Average Exercise Price (in usd per share) | $ 35.07
Minimum | Exercise Price Range $19.58 to $20.93 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Weighted-Average Exercise Price (in usd per share) | 19.58
Minimum | Exercise Price Range $21.50 to $21.99 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Weighted-Average Exercise Price (in usd per share) | 21.50
Minimum | Exercise Price Range $23.19 to $23.66 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Weighted-Average Exercise Price (in usd per share) | 23.19
Maximum | Exercise Price Range $19.58 to $20.93 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Weighted-Average Exercise Price (in usd per share) | 20.93
Maximum | Exercise Price Range $21.50 to $21.99 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Weighted-Average Exercise Price (in usd per share) | 21.99
Maximum | Exercise Price Range $23.19 to $23.66 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Weighted-Average Exercise Price (in usd per share) | $ 23.66

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- Definition The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(iii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(2) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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