Summary of Significant Accounting Policies - Maturities of Lease Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Maturities of lease liabilities:
2020 (excluding the three months ended March 31, 2020)	$ 13,376
2021	15,511
2022	13,261
2023	10,945
2024	9,436
Thereafter	36,982
Total Lease Payments	99,511
Less-Present Value Discount	(14,586)
Present Value of Lease Liabilities	84,925		$ 86,713
Supplemental information related to leases:
Cash paid for amounts included in the measurement of lease liabilities	4,473	$ 3,778
Lease right-of-use assets obtained in exchange for lease liabilities	$ 2,278	$ 174

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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-Publisher FASB
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-SubTopic 20
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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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