Lease Obligations	12 Months Ended
Dec. 31, 2018
Leases [Abstract]
Lease Obligations	Lease ObligationsThe Company and its subsidiaries use office space and equipment under leases expiring at various dates. These leases are considered operating leases for financial reporting purposes. Some of these leases have options to extend the length of the leases and contain clauses for cost of living, operating expense and real estate tax adjustments. Future minimum lease payments, without provision for sublease income, are: $46,592,000 in 2019; $43,504,000 in 2020; $39,061,000 in 2021; $34,444,000 in 2022, $30,881,000 in 2023 and $75,740,000 thereafter. Rental expense was $45,778,000, $52,925,000, and $47,453,000 for 2018, 2017, and 2016 respectively.

The entire disclosure for lessee entity's leasing arrangements including, but not limited to, all of the following: (a.) The basis on which contingent rental payments are determined, (b.) The existence and terms of renewal or purchase options and escalation clauses, (c.) Restrictions imposed by lease agreements, such as those concerning dividends, additional debt, and further leasing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-URI http://asc.fasb.org/subtopic&trid=77888251

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-URI http://asc.fasb.org/topic&trid=2208923

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