Stock Compensation - Summary of Transactions of Stock Option Plans (Details) - Stock Options - $ / shares	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Weighted-average exercise price
Options granted (in dollars per share)	$ 18.50	$ 14.38
Omnibus Incentive Plan
Number of shares
Beginning balance (in shares)	386,283	384,258	369,612
Options granted (in shares)	43,778	55,223	42,302
Options modified (in shares)	80,642
Options exercised (in shares)	(53,161)	(53,198)	(27,656)
Options canceled (ins shares)	(80,642)
Options forfeited (in shares)	0	0	0
Ending balance (in shares)	376,900	386,283	384,258
Exercisable options (in shares)	321,122	239,043	242,522
Weighted-average exercise price
Beginning balance (in dollars per share)	$ 25.74	$ 23.75	$ 22.35
Options granted (in dollars per share)	48.20	36.75	33.98
Options modified (in dollars per share)	52.44
Options exercised (in dollars per share)	21.47	22.83	20.59
Options canceled (in dollars per share)	37.04
Ending balance (in dollars per share)	28.95	25.74	23.75
Exercisable options (in dollars per share)	$ 27.16	$ 21.59	$ 21.01
Omnibus Incentive Plan \| Price range $ 18.08 — $ 19.21
Number of shares
Ending balance (in shares)	118,900
Weighted-average exercise price
Ending balance (in dollars per share)	$ 18.35
Price range - minimum (in dollars per share)	18.08
Price range - maximum (in dollars per share)	$ 19.21
Weighted-average contractual life	2 years 8 months 12 days
Omnibus Incentive Plan \| Price range $ 19.30 — $ 28.33
Number of shares
Ending balance (in shares)	119,139
Weighted-average exercise price
Ending balance (in dollars per share)	$ 27.17
Price range - minimum (in dollars per share)	19.30
Price range - maximum (in dollars per share)	$ 28.33
Weighted-average contractual life	5 years 3 months 18 days
Omnibus Incentive Plan \| Price range $ 28.34 — $ 48.20
Number of shares
Ending balance (in shares)	138,861
Weighted-average exercise price
Ending balance (in dollars per share)	$ 39.55
Price range - minimum (in dollars per share)	28.34
Price range - maximum (in dollars per share)	$ 48.20
Weighted-average contractual life	8 years 2 months 12 days

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Share based compensation arrangements by share based payment award options modified in period weighted average exercise price.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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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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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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Number of share options (or share units) exercised during the current period.

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