Stockholders' Equity - Stock Repurchases (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stockholders' Equity Note [Abstract]
Aggregate Number of Shares Repurchased (in shares)	43,751	31,225	21,202
Weighted Average Repurchase Price (in dollars per share)	$ 7.90	$ 25.61	$ 28.59
Value	$ 346	$ 800	$ 606

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration