Segment Reporting (Reconciliation Of Segment Assets To Consolidated Assets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting [Line Items]
Assets	$ 3,134,820	$ 2,893,546	$ 2,575,095
Deferred tax assets and income tax receivable	55,280	67,905	82,632
Agency [Member]
Segment Reporting [Line Items]
Assets	2,325,855	2,261,482	1,977,620
Principal [Member]
Segment Reporting [Line Items]
Assets	93,275	82,560	85,748
Finance [Member]
Segment Reporting [Line Items]
Assets	658,710	480,103	427,871
All Other [Member]
Segment Reporting [Line Items]
Assets	1,700	1,496	1,224
Total segment assets [Member]
Segment Reporting [Line Items]
Assets	$ 3,079,540	$ 2,825,641	$ 2,492,463