Name:	ori_EquitySecuritiesGrossUnrealizedGains
Namespace Prefix:	ori_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

This item represents the gross unrealized losses for equity securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

No definition available.

Name:	ori_EquitySecuritiesGrossUnrealizedLosses
Namespace Prefix:	ori_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

No definition available.

Name:	us-gaap_AvailableForSaleEquitySecuritiesAmortizedCostBasis
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount of equity securities categorized neither as held-to-maturity nor as trading.

No definition available.

Name:	us-gaap_AvailableForSaleSecuritiesEquitySecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.