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Current Accounting Developments Current Accounting Developments (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Marketable equity securities |  |  | $ 31,900
Cumulative effect of a change in accounting principle | [1] |  | (160)
Private Equity Funds |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Cost method investments |  | $ 11,400 |
Retained Earnings |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Cumulative effect of a change in accounting principle | [1] |  | (545)
Reclassification of tax effects in AOCI resulting from the new federal corporate income tax rate | [2] | 6,656 |
AOCI, Net of Tax |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Cumulative effect of a change in accounting principle | [1] |  | 385
Reclassification of tax effects in AOCI resulting from the new federal corporate income tax rate | [2] | $ (6,656) |
ASU 2016-01 | Retained Earnings |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Cumulative effect of a change in accounting principle |  |  | (545)
ASU 2016-01 | AOCI, Net of Tax |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Cumulative effect of a change in accounting principle |  |  | $ 385
[1] | Represents the impact of the adoption in the first quarter of 2018 of Accounting Standards Update (“ASU”) 2016-01, Financial Instruments — Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. Refer to Note 2 — Current Accounting Developments to the Consolidated Financial Statements for additional information.
[2] | Represents amounts reclassified from AOCI to retained earnings due to the early adoption of ASU 2018-02, Income Statement — Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income during the first quarter of 2018. Refer to Note 2 — Current Accounting Developments to the Consolidated Financial Statements for additional information.

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