Summary of Significant Accounting Policies - Maturities of Lease Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Maturities of lease liabilities:
2020	$ 17,124
2021	15,096
2022	12,873
2023	10,797
2024	9,222
Thereafter	36,954
Total Lease Payments	102,066
Less-Present Value Discount	(15,353)
Present Value of Lease Liabilities	86,713
Future minimum rental payments under noncancelable operating leases
2019		$ 13,503
2020		10,768
2021		9,449
2022		7,707
2023		6,402
Thereafter		28,328
Total future minimum rental payments		$ 76,157
Supplemental information related to leases:
Cash paid for amounts included in the measurement of lease liabilities	16,895
Lease right-of-use assets obtained in exchange for lease liabilities	$ 26,811

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