Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) shares in Thousands | Common Stock [Member] Common Class A [Member] | Common Stock [Member] Common Class B [Member] | Common Stock [Member] | Additional Paid-in Capital [Member] | Treasury Stock, Common [Member] | Retained Earnings [Member] Common Class A [Member] | Retained Earnings [Member] Common Class B [Member] | Retained Earnings [Member] | AOCI Attributable to Parent [Member] | Parent [Member] Common Class A [Member] | Parent [Member] Common Class B [Member] | Parent [Member] | Noncontrolling Interest [Member] | Common Class A [Member] | Common Class B [Member] | Total |
Balance (in shares) at Dec. 31, 2022 | 63,518 | 18,125 | | | | | | | | | | | | | | |
Balance at Dec. 31, 2022 | | | $ 572,000 | $ 500,642,000 | $ (130,930,000) | | | $ 1,378,337,000 | $ (4,130,000) | | | $ 1,744,491,000 | $ 18,531,000 | | | $ 1,763,022,000 |
Stock options exercised and stock awards (in shares) | 228 | | | | | | | | | | | | | | | |
Stock options exercised and stock awards | | | 2,000 | 3,412,000 | | | | | | | | 3,414,000 | | | | 3,414,000 |
Stock-based compensation related to stock options, restricted shares and employee stock purchase plan | | | | 13,080,000 | | | | | | | | 13,080,000 | | | | |
Vesting of restricted share awards (in shares) | | 422 | | | | | | | | | | | | | | |
Vesting of restricted share awards | | | 3,000 | (6,964,000) | | | | | | | | (6,961,000) | | | | (6,961,000) |
Issuance of common stock under employee stock purchase plan (in shares) | 102 | | | | | | | | | | | | | | | |
Issuance of common stock under employee stock purchase plan | | | | 2,828,000 | | | | | | | | 2,828,000 | | | | 2,828,000 |
Common stock repurchases (in shares) | (623) | (84) | | | | | | | | | | | | | | |
Common stock repurchases | | | | | (25,280,000) | | | | | | | (25,280,000) | | | | (25,280,000) |
Cash dividends declared | | | | | | $ (8,897,000) | $ (2,692,000) | | | $ (8,897,000) | $ (2,692,000) | | | | | |
Foreign currency translation adjustment | | | | | | | | | 232,000 | | | 232,000 | | | | |
Net income | | | | | | | | 90,455,000 | | | | 90,455,000 | 335,000 | | | |
Balance (in shares) at Mar. 31, 2023 | 63,225 | 18,463 | | | | | | | | | | | | | | |
Balance at Mar. 31, 2023 | | | 577,000 | 512,998,000 | (156,210,000) | | | 1,457,203,000 | (3,898,000) | | | 1,810,670,000 | 18,866,000 | | | 1,829,536,000 |
Balance (in shares) at Dec. 31, 2022 | 63,518 | 18,125 | | | | | | | | | | | | | | |
Balance at Dec. 31, 2022 | | | 572,000 | 500,642,000 | (130,930,000) | | | 1,378,337,000 | (4,130,000) | | | 1,744,491,000 | 18,531,000 | | | 1,763,022,000 |
Foreign currency translation adjustment | | | | | | | | | | | | | | | | (187,000) |
Net income | | | | | | | | | | | | | | | | 269,948,000 |
Balance (in shares) at Sep. 30, 2023 | 62,053 | 17,989 | | | | | | | | | | | | | | |
Balance at Sep. 30, 2023 | | | 804,000 | 533,648,000 | (16,169,000) | | | 1,385,646,000 | (4,317,000) | | | 1,899,612,000 | 19,471,000 | | | 1,919,083,000 |
Balance (in shares) at Mar. 31, 2023 | 63,225 | 18,463 | | | | | | | | | | | | | | |
Balance at Mar. 31, 2023 | | | 577,000 | 512,998,000 | (156,210,000) | | | 1,457,203,000 | (3,898,000) | | | 1,810,670,000 | 18,866,000 | | | 1,829,536,000 |
Stock options exercised and stock awards (in shares) | 237 | | | | | | | | | | | | | | | |
Stock options exercised and stock awards | | | 1,000 | 3,479,000 | | | | | | | | 3,480,000 | | | | 3,480,000 |
Stock-based compensation related to stock options, restricted shares and employee stock purchase plan | | | | 5,952,000 | | | | | | | | 5,952,000 | | | | 5,952,000 |
Vesting of restricted share awards | | | | (54,000) | | | | | | | | (54,000) | | | | (54,000) |
Common stock repurchases (in shares) | (890) | (195) | | | | | | | | | | | | | | |
Common stock repurchases | | | | | (40,305,000) | | | | | | | (40,305,000) | | | | (40,305,000) |
Cash dividends declared | | | | | | (8,812,000) | (2,725,000) | | | (8,812,000) | (2,725,000) | | | $ (8,812,000) | $ (2,725,000) | |
Foreign currency translation adjustment | | | | | | | | | 1,689,000 | | | 1,689,000 | | | | 1,689,000 |
Net income | | | | | | | | 98,275,000 | | | | 98,275,000 | 249,000 | | | 98,524,000 |
Balance (in shares) at Jun. 30, 2023 | 62,572 | 18,268 | | | | | | | | | | | | | | |
Balance at Jun. 30, 2023 | | | 578,000 | 522,375,000 | (196,515,000) | | | 1,543,941,000 | (2,209,000) | | | 1,868,170,000 | 19,115,000 | | | 1,887,285,000 |
Stock options exercised and stock awards (in shares) | 124 | | | | | | | | | | | | | | | |
Stock options exercised and stock awards | | | 1,000 | 1,888,000 | | | | | | | | 1,889,000 | | | | 1,889,000 |
Stock-based compensation related to stock options, restricted shares and employee stock purchase plan | | | | 6,265,000 | | | | | | | | 6,265,000 | | | | 6,265,000 |
Issuance of common stock under employee stock purchase plan (in shares) | 107 | | | | | | | | | | | | | | | |
Issuance of common stock under employee stock purchase plan | | | 1,000 | 3,123,000 | | | | | | | | 3,124,000 | | | | 3,124,000 |
Common stock repurchases (in shares) | (750) | (279) | | | | | | | | | | | | | | |
Common stock repurchases | | | | | (44,174,000) | | | | | | | (44,174,000) | | | | (44,174,000) |
Cash dividends declared | | | | | | (10,574,000) | (3,255,000) | | | (10,574,000) | (3,255,000) | | | (10,574,000) | (3,255,000) | |
Foreign currency translation adjustment | | | | | | | | | (2,108,000) | | | (2,108,000) | | | | (2,108,000) |
Net income | | | | | | | | 80,278,000 | | | | 80,278,000 | 356,000 | | | 80,634,000 |
Balance (in shares) at Sep. 30, 2023 | 62,053 | 17,989 | | | | | | | | | | | | | | |
Balance at Sep. 30, 2023 | | | 804,000 | 533,648,000 | (16,169,000) | | | 1,385,646,000 | (4,317,000) | | | 1,899,612,000 | 19,471,000 | | | 1,919,083,000 |
Retirement of treasury shares and par value adjustment | | | 224,000 | (3,000) | 224,520,000 | | | (224,744,000) | | | | (3,000) | | | | (3,000) |
Balance (in shares) at Dec. 31, 2023 | 61,461 | 16,364 | | | | | | | | | | | | | | |
Balance at Dec. 31, 2023 | | | 806,000 | 542,046,000 | (119,835,000) | | | 1,450,025,000 | (2,163,000) | | | 1,870,879,000 | | | | 1,890,416,000 |
Stock options exercised and stock awards (in shares) | 383 | | | | | | | | | | | | | | | |
Stock options exercised and stock awards | | | 4,000 | 5,997,000 | | | | | | | | 6,001,000 | | | | 6,001,000 |
Stock-based compensation related to stock options, restricted shares and employee stock purchase plan | | | | | | | | | | | | 14,090,000 | | | | |
Vesting of restricted share awards (in shares) | | 351 | | | | | | | | | | | | | | |
Vesting of restricted share awards | | | 4,000 | (9,486,000) | | | | | | | | (9,482,000) | | | | (9,482,000) |
Issuance of common stock under employee stock purchase plan (in shares) | 97 | | | | | | | | | | | | | | | |
Issuance of common stock under employee stock purchase plan | | | 1,000 | 3,354,000 | | | | | | | | 3,355,000 | | | | 3,355 |
Common stock repurchases (in shares) | (128) | | | | | | | | | | | | | | | |
Common stock repurchases | | | | | (5,627,000) | | | | | | | (5,627,000) | | | | (5,627,000) |
Cash dividends declared | | | | | | (10,467,000) | (2,964,000) | | | (10,467,000) | (2,964,000) | | | | | |
Foreign currency translation adjustment | | | | | | | | | (1,891,000) | | | (1,891,000) | | | | |
Net income | | | | | | | | 71,608,000 | | | | 71,608,000 | (119,000) | | | 71,489,000 |
Balance (in shares) at Mar. 31, 2024 | 61,813 | 16,715 | | | | | | | | | | | | | | |
Balance at Mar. 31, 2024 | | | 815,000 | 556,001,000 | (125,462,000) | | | 1,508,202,000 | (4,054,000) | | | 1,935,502,000 | 19,418,000 | | | 1,954,920,000 |
Balance (in shares) at Dec. 31, 2023 | 61,461 | 16,364 | | | | | | | | | | | | | | |
Balance at Dec. 31, 2023 | | | 806,000 | 542,046,000 | (119,835,000) | | | 1,450,025,000 | (2,163,000) | | | 1,870,879,000 | | | | 1,890,416,000 |
Foreign currency translation adjustment | | | | | | | | | | | | | | | | (1,806,000) |
Net income | | | | | | | | | | | | | | | | 229,692,000 |
Balance (in shares) at Sep. 30, 2024 | 62,308 | 16,695 | | | | | | | | | | | | | | |
Balance at Sep. 30, 2024 | | | 820,000 | 577,665,000 | (129,644,000) | | | 1,638,257,000 | (3,969,000) | | | 2,083,129,000 | 19,828,000 | | | 2,102,957,000 |
Balance (in shares) at Mar. 31, 2024 | 61,813 | 16,715 | | | | | | | | | | | | | | |
Balance at Mar. 31, 2024 | | | 815,000 | 556,001,000 | (125,462,000) | | | 1,508,202,000 | (4,054,000) | | | 1,935,502,000 | 19,418,000 | | | 1,954,920,000 |
Stock options exercised and stock awards (in shares) | 134 | | | | | | | | | | | | | | | |
Stock options exercised and stock awards | | | 1,000 | 2,098,000 | | | | | | | | 2,099,000 | | | | 2,099,000 |
Stock-based compensation related to stock options, restricted shares and employee stock purchase plan | | | | 5,515,000 | | | | | | | | 5,515,000 | | | | 5,515,000 |
Vesting of restricted share awards | | | | (10,000) | | | | | | | | (10,000) | | | | (10,000) |
Common stock repurchases (in shares) | (78) | (15) | | | | | | | | | | | | | | |
Common stock repurchases | | | | | (3,953,000) | | | | | | | (3,953,000) | | | | (3,953,000) |
Cash dividends declared | | | | | | (10,523,000) | (3,024,000) | | | (10,523,000) | (3,024,000) | | | (10,523,000) | (3,024,000) | |
Foreign currency translation adjustment | | | | | | | | | (873,000) | | | (873,000) | | | | (873,000) |
Net income | | | | | | | | 78,661,000 | | | | 78,661,000 | 122,000 | | | 78,783,000 |
Balance (in shares) at Jun. 30, 2024 | 61,869 | 16,700 | | | | | | | | | | | | | | |
Balance at Jun. 30, 2024 | | | 816,000 | 563,604,000 | (129,415,000) | | | 1,573,316,000 | (4,927,000) | | | 2,003,394,000 | 19,540,000 | | | 2,022,934,000 |
Stock options exercised and stock awards (in shares) | 341 | | | | | | | | | | | | | | | |
Stock options exercised and stock awards | | | 3,000 | 5,257,000 | | | | | | | | 5,260,000 | | | | 5,260,000 |
Stock-based compensation related to stock options, restricted shares and employee stock purchase plan | | | | 5,293,000 | | | | | | | | 5,293,000 | | | | 5,293,000 |
Issuance of common stock under employee stock purchase plan (in shares) | 99 | | | | | | | | | | | | | | | |
Issuance of common stock under employee stock purchase plan | | | 1,000 | 3,511,000 | | | | | | | | 3,512,000 | | | | 3,512,000 |
Common stock repurchases (in shares) | (1) | (5) | | | | | | | | | | | | | | |
Common stock repurchases | | | | | (229,000) | | | | | | | (229,000) | | | | (229,000) |
Cash dividends declared | | | | | | $ (11,185,000) | $ (3,006,000) | | | $ (11,185,000) | $ (3,006,000) | | | $ (11,185,000) | $ (3,006,000) | |
Foreign currency translation adjustment | | | | | | | | | 958,000 | | | 958,000 | | | | 958,000 |
Net income | | | | | | | | 79,132,000 | | | | 79,132,000 | 288,000 | | | 79,420,000 |
Balance (in shares) at Sep. 30, 2024 | 62,308 | 16,695 | | | | | | | | | | | | | | |
Balance at Sep. 30, 2024 | | | $ 820,000 | $ 577,665,000 | $ (129,644,000) | | | $ 1,638,257,000 | $ (3,969,000) | | | $ 2,083,129,000 | $ 19,828,000 | | | $ 2,102,957,000 |