Long-Term Debt and Short-Term Borrowings - Summary of cumulative effect adjustment upon adoption (Details) - USD ($) $ in Thousands	Jul. 01, 2021	Jan. 01, 2021	Dec. 31, 2020
Long-term debt	$ 283,893		$ 193,036
Deferred income taxes	21,960		33,429
Capital in excess of par	140,916		153,529
Retained earnings	$ 281,102		$ 331,897
Accounting Standards Update 2020-06 [Member] \| Cumulative effect period of adoption adjustment
Long-term debt		$ 21,393
Deferred income taxes		(5,584)
Capital in excess of par		(16,511)
Retained earnings		702
Accounting Standards Update 2020-06 [Member] \| Balance at January 1, 2021
Long-term debt		214,429
Deferred income taxes		27,845
Capital in excess of par		137,018
Retained earnings		$ 332,599

Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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