Subsequent Events	12 Months Ended
Dec. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	Note C— Subsequent Events The Company evaluated its December 31, 2021 consolidated financial statements for subsequent events through the date the consolidated financial statements were issued. Pursuant to a stock repurchase plan described in Note J, the Company repurchased 527,393 common shares in January and February of 2022, at a total cost of $15.0 million and an average price of $28.44 per share. On January 28, 2022, the Company signed a lease for approximately 52,000 square feet to relocate its Sioux Falls office to a new Sioux Falls location, for a minimum period of 10 years, which can be extended. Estimated occupancy is mid-2023 when rent payments, which begin at $24 per square foot, will increase throughout that 10 year period and amount to $28.68 in year 10.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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