Benefit Plans - Information about Stock Options Outstanding (Details) - 2016 Plan - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Shares
Outstanding at beginning of period (in shares)	185,003	210,448
Granted (in shares)	0	10,556
Exercised (in shares)	0	(10,511)
Forfeited (in shares)	0	(25,490)
Outstanding at end of period (in shares)	185,003	185,003
Nonvested at end of period	79,497	116,072
Exercisable at end of period (in shares)	105,506	68,931
Weighted-average fair value of awards granted (in usd per share)	$ 0.00	$ 4.24
Weighted- Average Exercise Price
Outstanding at beginning of period (in usd per share)	13.56	13.27
Granted (in usd per share)	0.00	17.6500
Exercised (in usd per share)	0.00	13.04
Forfeited (in usd per share)	0.00	13.04
Outstanding at end of period (in usd per share)	13.56	13.56
Nonvested at end of period (in usd per share)	13.88	13.73
Exercisable at end of period (in usd per share)	$ 13.32	$ 13.25

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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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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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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Gross 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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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 that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of non-vested options outstanding.

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Weighted average grant-date fair value of non-vested options outstanding.

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

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