XML 33 R20.htm IDEA: XBRL DOCUMENT
v3.22.4

Net Investment Gains | 12 Months Ended
--- | ---
Dec. 31, 2022
Realized and Unrealized Investment Gains (Losses) [Abstract] |
Net Investment Gains | Net Investment Gains Net investment gains were as follows:
(In thousands) | 2022 |  | 2021 |  | 2020
Net investment gains: |  |  |  |  |
Fixed maturity securities: |  |  |  |  |
Gains | $ | 4,224 |  |  | $ | 18,981 |  |  | $ | 27,819 |
Losses | (11,654) |  |  | (6,975) |  |  | (56,096) |
Equity securities (1): |  |  |  |  |
Net realized (losses) gains on investment sales | (12,879) |  |  | 16,365 |  |  | 32,647 |
Change in unrealized losses | (632) |  |  | (38,455) |  |  | (25,868) |
Investment funds | 12,407 |  |  | 44,778 |  |  | 31,481 |
Real estate (2) | 293,525 |  |  | 94,911 |  |  | 101,554 |
Loans receivable | (32) |  |  | (881) |  |  | — |
Other | (67,648) |  |  | (21,766) |  |  | (38,023) |
Net realized and unrealized gains on investments in earnings before allowance for expected credit losses | 217,311 |  |  | 106,958 |  |  | 73,514 |
Change in allowance for expected credit losses on investments: |  |  |  |  |
Fixed maturity securities | (14,841) |  |  | (20,045) |  |  | 33,134 |
Loans receivable | (73) |  |  | 3,719 |  |  | (3,648) |
Change in allowance for expected credit losses on investments | (14,914) |  |  | (16,326) |  |  | 29,486 |
Net investment gains | 202,397 |  |  | 90,632 |  |  | 103,000 |
Income tax expense | (42,670) |  |  | (17,710) |  |  | (21,630) |
After-tax net investment gains | $ | 159,727 |  |  | $ | 72,922 |  |  | $ | 81,370 |
Change in unrealized investment (losses) gains: |  |  |  |  |
Fixed maturity securities without allowance for expected credit losses | $ | (1,216,292) |  |  | $ | (262,221) |  |  | $ | 134,129 |
Fixed maturity securities with allowance for expected credit losses | (28,370) |  |  | 10,124 |  |  | 32,004 |
Investment funds | (2,019) |  |  | (1,270) |  |  | 2,280 |
Other | (1,447) |  |  | (1,572) |  |  | (3,768) |
Total change in unrealized investment (losses) gains | (1,248,128) |  |  | (254,939) |  |  | 164,645 |
Income tax benefit (expense) | 264,325 |  |  | 56,127 |  |  | (24,395) |
Noncontrolling interests | (2) |  |  | (2) |  |  | (2) |
After-tax change in unrealized investment (losses) gains | $ | (983,805) |  |  | $ | (198,814) |  |  | $ | 140,248 |
____________________ (1) The net realized gains or losses on investment sales represent the total gains or losses from the purchase dates of the equity securities. The change in unrealized (losses) gains consists of two components: (i) the reversal of the gain or loss recognized in previous periods on equity securities sold and (ii) the change in unrealized gain or loss resulting from mark-to-market adjustments on equity securities still held. (2) During March 2022, the Company realized a gain on the sale of a real estate investment in London, U.K. of $251 million, net of transaction expenses and the foreign currency impact, including the reversal of the currency translation adjustment.

X
- Definition The entire disclosure for cash, cash equivalents, investments in debt and equity instruments (including cost and equity investees and related income statement amounts), equity and cost method investments, investments in joint ventures and any other investment. + References No definition available. + Details
Name: | us-gaap_InvestmentsInDebtAndEquityInstrumentsCashAndCashEquivalentsUnrealizedAndRealizedGainsLossesTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Realized and Unrealized Investment Gains (Losses) [Abstract] + References No definition available. + Details
Name: | wrb_RealizedAndUnrealizedInvestmentGainsLossesAbstract
Namespace Prefix: | wrb_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration