| Income Tax Disclosure [Abstract] | Period [Axis] |
|---|
2016-01-01 - 2016-12-31 |
|---|
Income Tax Disclosure [Abstract] | |
Sources of income from continuing operations before income taxes | The sources of income from continuing operations before income taxes and earnings of unconsolidated equity method investment for the years ended December 31, 2016, 2015 and 2014 were as follows: | | | | | | | | | | | | | | Year Ended December 31, | | 2016 | | 2015 | | 2014 | U.S. operations | $ | 2,230 |
| | $ | 2,433 |
| | $ | 2,047 |
| Non-U.S. operations | 154,275 |
| | 125,810 |
| | 109,590 |
| Income from continuing operations before income taxes and earnings of unconsolidated equity method investment | $ | 156,505 |
| | $ | 128,243 |
| | $ | 111,637 |
|
|
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] | The components of the income tax provision from continuing operations for the year ended December 31, 2016, 2015 and 2014 consisted of the following: | | | | | | | | | | | | | | Year Ended December 31, | | 2016 | | 2015 | | 2014 | Current: | | | | | | United States: | | | | | | Federal | $ | 2,004 |
| | $ | 4,167 |
| | $ | 1,571 |
| State | 587 |
| | 994 |
| | 390 |
| Non-U.S | 3,560 |
| | 14,499 |
| | 9,040 |
| Current income tax provision | 6,151 |
| | 19,660 |
| | 11,001 |
| Deferred: | | | | | | United States: | | | | | | Federal | 1,350 |
| | 829 |
| | 2,335 |
| State | (157 | ) | | 57 |
| | 932 |
| Non-U.S | 4,963 |
| | (7,775 | ) | | (405 | ) | Deferred income tax provision (benefit) | 6,156 |
| | (6,889 | ) | | 2,862 |
| Total | $ | 12,307 |
| | $ | 12,771 |
| | $ | 13,863 |
|
|
Schedule of Deferred Tax Assets and Liabilities [Table Text Block] | Significant components of the Company’s deferred tax assets and liabilities at December 31, 2016, 2015 and 2014 consisted of the following: | | | | | | | | | | | | | | Year Ended December 31, | | 2016 | | 2015 | | 2014 | Deferred tax assets: | | | | | | Non-cash share-based payments | $ | 2,183 |
| | $ | 1,483 |
| | $ | 1,106 |
| Net operating loss carry forwards | 47,538 |
| | 52,007 |
| | 42,900 |
| Other | 1,902 |
| | 761 |
| | 375 |
| Total deferred tax assets | 51,623 |
| | 54,251 |
| | 44,381 |
| Deferred tax liabilities: | | | | | | Accelerated depreciation | (92,734 | ) | | (87,716 | ) | | (79,360 | ) | Other | (1,227 | ) | | (442 | ) | | (1,795 | ) | Total deferred tax liabilities | (93,961 | ) | | (88,158 | ) | | (81,155 | ) | Net deferred tax liabilities | $ | (42,338 | ) | | $ | (33,907 | ) | | $ | (36,774 | ) |
|
Analysis of effective income tax rate for continuing operations | Differences between statutory income tax rates and our effective income tax rates applied to pre-tax income from continuing operations at December 31, 2016, 2015 and 2014 consisted of the following: | | | | | | | | | | | | | | Year Ended December 31, | | 2016 | | 2015 | | 2014 | Notional U.S. federal income tax expense at the statutory rate: | $ | 54,777 |
| | $ | 44,885 |
| | $ | 39,073 |
| U.S. state and local income tax, net | 182 |
| | 221 |
| | 189 |
| Non-U.S. operations: | | | | | | Bermuda | (31,250 | ) | | (20,789 | ) | | (12,424 | ) | Ireland | (276 | ) | | (3,073 | ) | | (4,732 | ) | Singapore | (7,519 | ) | | (5,650 | ) | | (5,529 | ) | Other low tax jurisdictions | (3,877 | ) | | (3,395 | ) | | (2,890 | ) | Non-deductible expenses in the U.S. | 525 |
| | 737 |
| | 644 |
| Other | (255 | ) | | (165 | ) | | (468 | ) | Provision for income taxes | $ | 12,307 |
| | $ | 12,771 |
| | $ | 13,863 |
|
|