Segment Reporting (Schedule of Automotive and Other Segment Reporting) (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Revenues	$ 529,864,000	$ 474,639,000	$ 229,926,000	$ 453,762,000	$ 443,836,000	$ 477,761,000	$ 468,711,000	$ 468,589,000	$ 1,688,189,405	$ 1,858,897,406	$ 1,834,063,697
Income (Loss) from Operations	162,414,000	$ 138,853,000	$ (6,738,000)	$ 105,027,000	110,901,000	$ 128,136,000	$ 127,905,000	$ 121,596,000	399,556,092	488,537,604	508,125,547
Assets	2,197,941,170				2,168,803,193				2,197,941,170	2,168,803,193	2,085,434,068
Depreciation & Amortization									104,739,900	104,702,974	102,186,814
Capital Expenditures									51,706,541	84,580,255	85,990,570
Corporate
Segment Reporting Information [Line Items]
Assets	728,248,906				689,772,238				728,248,906	689,772,238	621,190,035
Depreciation & Amortization									6,519,815	6,700,141	4,484,918
Capital Expenditures									15,309,150	19,338,698	205,621
Automotive Products
Segment Reporting Information [Line Items]
Revenues									1,648,198,143	1,810,536,887	1,791,198,296
Income (Loss) from Operations									393,979,860	473,546,112	495,471,799
Automotive Products | Operating Segments
Segment Reporting Information [Line Items]
Assets	1,436,374,596				1,463,030,286				1,436,374,596	1,463,030,286	1,449,910,935
Depreciation & Amortization									97,530,191	97,520,972	97,279,052
Capital Expenditures									34,926,686	63,537,512	84,337,455
Other
Segment Reporting Information [Line Items]
Revenues									39,991,262	48,360,519	42,865,401
Income (Loss) from Operations									5,576,232	14,991,492	12,653,748
Other | Operating Segments
Segment Reporting Information [Line Items]
Assets	$ 33,317,668				$ 16,000,669				33,317,668	16,000,669	14,333,098
Depreciation & Amortization									689,894	481,861	422,844
Capital Expenditures									1,470,705	1,704,045	1,447,494
United States | Automotive Products
Segment Reporting Information [Line Items]
Revenues									519,337,271	569,939,756	583,672,971
Germany | Automotive Products
Segment Reporting Information [Line Items]
Revenues									228,652,827	296,276,971	333,002,878
Japan | Automotive Products
Segment Reporting Information [Line Items]
Revenues									216,100,530	225,577,146	209,311,790
Mexico | Automotive Products
Segment Reporting Information [Line Items]
Revenues									127,157,684	160,967,900	106,111,515
Other Countries | Automotive Products
Segment Reporting Information [Line Items]
Revenues									$ 556,949,831	$ 557,775,114	$ 559,099,142