| 11. | INCOME TAXES |
| a. | Income Before Income Taxes |
| | | 2017 | | | 2016 | | | 2015 | | |||
| Domestic | | $ | 121,897 | | | $ | 185,042 | | | $ | 163,325 | |
| Foreign | | | 641 | | | | 375 | | | | (14 | ) |
| Total income before income taxes | | $ | 122,538 | | | $ | 185,417 | | | $ | 163,311 | |
| b. | Income Tax Expense |
| | | 2017 | | | 2016 | | | 2015 | | |||
| Current | | | | | | | | | | | | |
| Federal | | $ | 21,316 | | | $ | 51,489 | | | $ | 58,090 | |
| State | | | 4,327 | | | | 10,307 | | | | 8,627 | |
| Foreign | | | 155 | | | | 144 | | | | 54 | |
| | | $ | 25,798 | | | $ | 61,940 | | | $ | 66,771 | |
| Deferred | | | | | | | | | | | | |
| Federal | | $ | (16,065 | ) | | $ | 3,448 | | | $ | (7,930 | ) |
| State | | | 1,459 | | | | 686 | | | | 288 | |
| Foreign | | | (76 | ) | | | (90 | ) | | | (107 | ) |
| | | $ | (14,682 | ) | | $ | 4,044 | | | $ | (7,749 | ) |
| Total consolidated expense | | $ | 11,116 | | | $ | 65,984 | | | $ | 59,022 | |
| | | 2017 | | | 2016 | | | 2015 | | |||
| Pretax book income | | $ | 122,538 | | | $ | 185,417 | | | $ | 163,311 | |
| | | | | | | | | | | | | |
| Federal tax expense at 35% statutory rate | | | 42,888 | | | | 64,896 | | | | 57,159 | |
| State and local income taxes (net of federal benefit) | | | 5,047 | | | | 7,145 | | | | 6,190 | |
| Benefit of domestic production deduction | | | (3,450 | ) | | | (5,065 | ) | | | (5,255 | ) |
| Change in income tax reserves | | | (11,925 | ) | | | 862 | | | | 641 | |
| Remeasurement of deferred taxes | | | (19,796 | ) | | | - | | | | - | |
| Other | | | (1,648 | ) | | | (1,854 | ) | | | 287 | |
| Total income tax expense | | $ | 11,116 | | | $ | 65,984 | | | $ | 59,022 | |
| c. | Deferred Taxes |
| | | 2017 | | | 2016 | | ||
| Deferred tax assets | | | | | | | | |
| Tax credits and loss carryforwards | | $ | 1,710 | | | $ | 260 | |
| Accrued liabilities | | | 6,629 | | | | 9,852 | |
| Incentive compensation | | | 13,867 | | | | 21,206 | |
| Other | | | 2,852 | | | | 4,084 | |
| | | $ | 25,058 | | | $ | 35,402 | |
| Deferred tax liabilities | | | | | | | | |
| Property, plant and equipment | | $ | (12,813 | ) | | $ | (5,823 | ) |
| Intangibles | | | (45,960 | ) | | | (5,299 | ) |
| Other | | | (2,003 | ) | | | (3,264 | ) |
| | | $ | (60,776 | ) | | $ | (14,386 | ) |
| | | | | | | | | |
| Net deferred tax asset before valuation allowances and reserves | | $ | (35,718 | ) | | $ | 21,016 | |
| Valuation allowances | | | (1,237 | ) | | | (1,172 | ) |
| Net deferred tax asset or liability | | $ | (36,955 | ) | | $ | 19,844 | |
| d. | Tax Reserves |
| Balance at January 1, 2016 | | $ | 10,625 | |
| | | | | |
| Decrease in prior year tax positions | | | - | |
| | | | | |
| Balance at December 31, 2016 | | $ | 10,625 | |
| | | | | |
| Decrease in prior year tax positions | | | (10,130 | ) |
| | | | | |
| Balance at December 31, 2017 | | $ | 495 |