Significant Accounting Policies (Details Textual)							3 Months Ended		12 Months Ended
	May 01, 2024	Jan. 18, 2018 USD ($)	Apr. 01, 2017	May 03, 2016	Oct. 23, 2014 USD ($)	Mar. 28, 2012	Mar. 31, 2018 USD ($) Clients shares	Mar. 31, 2017 USD ($) Clients	Dec. 31, 2017 USD ($) Clients shares
Significant Accounting Policies [Line Items]
Net cash provided by (used in) operating activities							$ (61,033,000)	$ (33,218,000)
Payment for contingent consideration								$ 5,183,000
Clients exceeding consolidated accounts receivable percentage | Clients							0		0
Consolidated accounts receivable percentage							10.00%		10.00%
Clients exceeding consolidated largest client revenue | Clients							0	0
Consolidated largest client revenue (percent)							10.00%	10.00%
Impairment of long-lived asset							$ 2,317,000	$ 0
Cost method investments							9,462,000		$ 9,527,000
Goodwill							832,510,000		835,935,000
Acquisition related costs							376,000	234,000
Assets							1,701,077,000		1,698,892,000
Liabilities							1,836,394,000		1,791,519,000
Adjustment to deferred acquisition consideration included in interest expense							11,000	29,000
Provisional tax expense									(26,674,000)
Doner
Significant Accounting Policies [Line Items]
Voting interest in variable interest entity (percent)			65.00%			30.00%
Assets							96,659,000		105,191,000
Liabilities							$ 50,997,000		$ 59,783,000
Doner
Significant Accounting Policies [Line Items]
Ownership interest percentage increase on exercise of option			15.00%
Aggregate 2012 Acquisitions | Doner
Significant Accounting Policies [Line Items]
Ownership interest percentage increase on exercise of option						70.00%
Aggregate 2017 Step-up Transaction | Doner
Significant Accounting Policies [Line Items]
Ownership interest percentage increase on exercise of option			85.00%
Minimum
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life							3 years
Contract termination notice period							30 days
Contract payment term							30 days
Maximum
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life							7 years
Equity method investment, ownership percentage (percent)							50.00%
Contract termination notice period							90 days
Contract payment term							60 days
Wells Fargo Capital Finance, LLC
Significant Accounting Policies [Line Items]
Debt instrument, maturity date				May 03, 2021	Sep. 30, 2019
Maximum borrowing capacity					$ 325,000,000
Contingent Payment
Significant Accounting Policies [Line Items]
Change in contingent purchase price obligation							$ 2,586,000	11,431,000
6.50% Notes due 2024
Significant Accounting Policies [Line Items]
Interest rate, stated percentage							6.50%
Restricted Stock Units (RSUs) | Common Class A
Significant Accounting Policies [Line Items]
Stock issued during period (shares) | shares							74,950
Restricted stock grant date fair value							$ 681,000
Forecast | 6.50% Notes due 2024 | Wells Fargo Capital Finance, LLC
Significant Accounting Policies [Line Items]
Debt instrument, maturity date	May 01, 2024
Stock Incentive Plan 2011 | Contingent Restricted Stock Units (RSUs)
Significant Accounting Policies [Line Items]
Stock issued during period, restricted stock award (shares) | shares							413,181
RSUs outstanding (shares) | shares							930,600
Stock Incentive Plan 2016 | Contingent Restricted Stock Units (RSUs)
Significant Accounting Policies [Line Items]
RSUs outstanding (shares) | shares							503,321
Aggregate grant date fair value		$ 4,514,000
Preferred Stock | Series 4 Convertible Preferred Stock
Significant Accounting Policies [Line Items]
Shares outstanding (shares) | shares							95,000		95,000
Accounting Standards Update 2016-15
Significant Accounting Policies [Line Items]
Net cash provided by (used in) operating activities								$ (2,542,000)
Canada
Significant Accounting Policies [Line Items]
Effective tax rate (percent)							24.10%